Retail Media Networks Face Accountability and Growth Challenges

Retail media is experiencing a period of rapid expansion, yet advertisers are increasingly questioning the true impact of their spending as the industry lacks a consistent method for proving performance [1]. While many platforms report strong results, the reliance on varied attribution models has created a fragmented environment where it is difficult to distinguish between genuine growth and existing demand [1].

Key takeaways

• US retail media spend is projected to reach $69.33 billion by 2026, with Amazon and Walmart expected to capture over 89% of that growth [2].
• Advertisers are turning to incrementality—measuring the causal impact of ads compared to a control group—to determine if purchases would have occurred without advertising [1].
• Ghost ads, which use neutral placeholders in auctions to create valid control groups, are being adopted to improve the precision of lift studies [1].
• The IAB warns that many retail media networks face an "implicit sorting" by the market if they fail to make explicit strategic choices regarding their business models [2].

The Challenge of Proving Performance

The current retail media landscape is characterized by a "scale problem," where each network utilizes its own rules for attribution, lookback windows, and return on ad spend (ROAS) interpretations [1]. Because most measurement relies on crediting conversions to ad exposure, advertisers often struggle to identify whether an ad actually drove a sale or simply appeared to a shopper who was already planning to purchase [1]. This ambiguity makes it difficult to compare performance across different networks, as budget decisions are frequently based on inconsistent methodologies rather than objective outcomes [1].

To address these concerns, marketers are increasingly prioritizing incrementality, which isolates the true lift of a campaign by comparing outcomes between a group that sees an ad and a control group that does not [1]. Platforms like DoorDash have begun implementing "ghost ads"—a methodology that keeps control groups within the auction process to maintain natural dynamics—to provide more reliable data [1]. This approach has reportedly led to a 92% reduction in experimentation dilution and a 35% improvement in ROAS confidence intervals for the platform [1].

Strategic Choices in a Crowded Market

Beyond measurement, the industry is grappling with a saturation of retail media networks, as a database maintained by Mimbi currently tracks 270 networks worldwide [2]. With global market leaders expected to account for 57% of all sales growth between 2025 and 2030, many smaller networks are finding it difficult to compete for national brand budgets [2].

The IAB suggests that networks must move away from a default "scale-at-all-costs" mentality, which is often driven by unrealistic forecasts presented to boards [2]. Instead, the industry is seeing a shift toward more sustainable paths, such as treating media as a margin lever rather than a primary growth engine, or focusing on specialized, lean operations [2].

Why it matters

The transition toward incrementality and strategic refinement marks a shift in the retail media ecosystem from a focus on raw scale to a focus on accountability and trust [1]. As advertisers gain access to more rigorous measurement tools, they are better positioned to direct investment toward platforms that deliver genuine value [1]. For the networks themselves, this evolution means that those failing to provide clear, causal evidence of their impact may find themselves marginalized as the market sorts winners from losers over the next two to three years [2].