Post-Cookie Ads: Retail Media Networks Become the New Walled Gardens

Post-Cookie Ads: Retail Media Networks Become the New Walled Gardens for a decade, the open web ran on third-party cookies tiny trackers that followed users across sites and powered the programmatic ad boom. Now, that era is fading. Safari and Firefox already restrict third-party cookies by default, and Chrome is tightening tracking with its Privacy Sandbox and new protections, even after delaying or softening full cookie deprecation multiple times. 

But instead of killing targeted advertising, these privacy shifts are accelerating a different model: retail media networks (RMNs)—closed, data-rich ad platforms run by retailers and marketplaces. Global retail media ad spend is projected to reach roughly $165.9 billion in 2025, more than triple 2019 levels, with year-on-year growth around 15–20%, far outpacing the broader ad market. 

From Amazon in the US to Flipkart and Myntra in India, these networks are becoming the new walled gardens: powerful, closed ecosystems where retailers own the data, the inventory, and increasingly the rules.

1. Cookies didn’t disappear—but the signal did

Google originally planned to phase out third-party cookies in Chrome by 2024, then shifted the timeline to early 2025. Under regulatory pressure and industry pushback, the company has since moved toward a more gradual approach: restrictions, new Privacy Sandbox APIs, and stronger tracking protections (especially in Incognito), rather than a hard “off” switch. 

Meanwhile:

• Safari and Firefox already block most third-party cookies by default.
  
• Regulators and data-protection laws (GDPR, CCPA and similar) are squeezing “wild west” third-party data brokers, forcing higher transparency, consent and governance.
  

So even though some cookies technically remain, signal quality has collapsed:

• Cross-site tracking is harder.
  
• Frequency capping and attribution across the open web are less reliable.
  
• Third-party segments are under scrutiny for consent and accuracy.
  

This is the vacuum retail media networks are rushing to fill—with first-party, consented shopper data.

2. The retail media boom, by the numbers

Retail media means ad inventory sold by retailers and marketplaces, typically around search, product listings, and display on their apps, websites, and now connected TV. Brands love it because each impression is tied to real purchase behaviour.

Key growth signals:

• Global retail media spend is expected to grow from about $50.7B (2019) to ~$165.9B in 2025, roughly 3.3× growth.
  
• In the US alone, retail media is forecast to hit about $60B in 2025 and reach $100B by 2028, growing ~20% in 2025 vs ~4–5% for total ad spend.
  
• Dentsu estimates global retail media ad spend will grow 13.9% in 2025, faster than social, search or programmatic overall.
  
• Amazon remains the dominant force: one forecast expects $60.6B in retail media ad revenue in 2025 (excluding Prime Video/Twitch), heading toward nearly $70B in 2026.
  
• In India, leading e-commerce platforms Amazon, Flipkart and Myntra generated about ₹15,573 crore (~$1.9B) in ad revenues in FY25, up 26% year-on-year, underlining how retail media is now a core profit engine, not a side business.
  

This money is coming directly from post-cookie reallocation: trade marketing, shopper marketing, open-web display and even some TV budgets are shifting into RMNs that promise “closed-loop” performance—see ad, click, and purchase in one system. 

3. Why retail media networks are the new walled gardens

In theory, privacy changes should have reduced the power of walled gardens (Google, Meta). In reality, we’re getting more walled gardens, not fewer—just run by retailers.

a) First-party data moats

Retailers see every step of the shopping journey:

• Searches (“toothpaste for kids”, “sugar-free biscuits”)
  
• Browsing behaviour (categories, price filters, brand preferences)
  
• Actual purchases, returns, and frequency
  

Because this is first-party data, collected on their own properties with consent, it remains usable even as third-party cookies fade. 

Brands cannot easily replicate that fidelity across the open web—so they must pay the retailer to access those audiences.

b) Closed-loop measurement

RMNs offer what open-web programmatic often struggled to:

• On-platform attribution (“this keyword drove this basket”)
  
• SKU-level reporting
  
• Near real-time optimisation of bids and product placement
  

This is exactly what marketers crave as cookies weaken—but it also means measurement lives inside the retailer’s reporting, with limited external verification. 

c) Self-preferencing & rent extraction

Because the retailer controls search rankings, sponsored slots and product recommendations, they can:

• Charge high CPCs for “must-win” keywords (e.g., “detergent”, “smartphone”).
  
• Favour their own private labels in both organic and paid visibility.
  
• Bundle ad spend with trade terms (“to get better shelf space on the app, increase your retail media budget”).
  

Over time, this creates a closed economic loop where brands have little choice but to keep investing—similar to how advertisers once felt about Facebook’s News Feed or Google Search.

d) Limited interoperability

Retail media data is rarely portable:

• Audience segments built on Amazon rarely move to Walmart or an open-web DSP.
  
• Clean rooms and APIs exist, but are tightly controlled and often expensive.
  

So even as third-party cookies decline, cross-platform frequency and reach planning remain fragmented, locking spend into each garden. 

4. The new ad stack: Search, off-site, and streaming inside RMNs

The “new walled gardens” are not just banner ads on retail sites—they’re building full ad ecosystems:

1. On-site search & sponsored listings
   
   • The core of retail media: sponsored products, brand zones, display on category pages, and homepage takeovers.
     
2. Off-site retail media
   
   • Using first-party shopper data to buy ads on the open web (websites, social, even CTV) via demand-side platforms, with attribution still reported back through the retailer.
     
3. Streaming & CTV as retail media
   
   • Amazon is integrating retail data with Prime Video ads, which now reach 315M monthly ad-supported viewers globally, making TV ads shoppable and precisely targeted.
     
4. In-store and omnichannel
   
   • In matured markets, in-store screens, digital shelf tags and even receipts are being folded into RMN buys, connecting online and offline sales data.
     

The result: retailers start to resemble full-stack media companies, with their own ad tech, measurement, and content.

5. Risks: Fragmentation, dependence, and fairness concerns

This shift brings real efficiency—but also real risks.

• Brand dependence
  
  Mid-size brands can become dependent on one or two RMNs for growth, giving retailers leverage on pricing and terms.
  
• Publisher squeeze
  
  As more budgets flow into RMNs, open-web publishers (news, independent content creators) lose share of ad spend, challenging media pluralism.
  
• Competition & regulation
  
  Regulators already worry about large platforms combining commerce, data and ads. Google faces antitrust rulings on its ad tech stack; similar questions are starting to surface around retail giants’ media operations.
  
• Consumer fairness & dark patterns
  
  If search results and recommendations are heavily pay-to-play, shoppers may effectively see a distorted shelf, not a neutral one—raising questions about transparency and consumer protection.
  

6. What smart advertisers should do now

For brands and agencies, the answer is not “ignore retail media”—it’s use it with eyes open:

1. Balance ROAS with dependency
   
   • Invest in RMNs for performance, but avoid concentrating spend on a single retailer.
     
   • Negotiate for data access, experimentation budgets, and transparency.
     
2. Build your own first-party data spine
   
   • Loyalty programs, CRM, apps, and direct-to-consumer channels remain essential.
     
   • Connect your own IDs with RMN reporting via clean rooms where possible, rather than relying only on their dashboards.
     
3. Push for standards and verification
   
   • Where industry bodies or measurement partners offer cross-retailer metrics, support them.
     
   • Ask for incrementality tests, not just click-through reports.
     
4. Protect smaller brands and consumers
   
   • For portfolios, ensure retail media strategies don’t only favour top SKUs.
     
   • Avoid overly intrusive or manipulative targeting that can trigger backlash or regulatory risk.
     

Ads, data and Dharma in a post-cookie world

From a Satgyan viewpoint, as explained by spiritual giant Sant Rampal Ji Maharaj, the deeper question is not just “where do ads run now?”, but “are we using knowledge and technology with Dharma (righteousness) or only for lobh (greed)?”

Three reflections:

• Ads should not hide behind dark patterns, fake scarcity or manipulated reviews.
  
• If walled gardens quietly exaggerate effectiveness or distort search results for money, it becomes a form of commercial untruth that misleads both brands and consumers.
  
  
• When a handful of platforms control data and shelf visibility, small brands and local sellers can be pushed into invisibility unless they pay.
  
• A Dharmic approach would seek fair rules, transparent auctions, and opportunities for MSMEs—not only for global giants.
  
  
• Hyper-precise data can be used to help people (e.g., surface genuinely better, healthier, affordable choices) or to nudge them into over-consumption, toxic products, or debt.
  
• Satgyan reminds us that true welfare means designing systems that respect human dignity, privacy and well-being, not treating people as just “clicks” or “ARPU.”
  

If brands, retailers and regulators align on these principles, retail media networks can become tools for efficient, honest commerce rather than new centres of hidden exploitation.

Read Also: How to Sell Online: A Step-by-Step Guide for Beginners

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