Why retail media supply-side platforms alone won’t save your ad business

Retail media is the fastest-growing sector of digital advertising, with spend rising over 20% year over year.
However, two myths hinder RMNs: 'too many RMNs' causing fragmentation, and 'RMNs need external demand.' A common misguided solution is building a retail media SSP, which manages multiple demand sources.
However, SSPs fail to scale because they don't improve existing inventory performance, lack ML-driven relevance for 1:1 personalization, and shift performance risk to advertisers.
In programmatic RTB, RMNs risk commoditizing inventory as advertisers optimize across competitors.
This leads to low budget utilization and fill rates.
Moreover, most revenue comes from endemic advertisers, shaping strategies around a smaller subset of demand.
SSPs were designed for a different scale than retail media, where advertisers typically focus on 10-20 key RMNs.
RMNs are mini walled gardens with unique advantages: transaction-close inventory, best first-party data, and built-in brand relationships.
To scale, they should follow the playbook of Amazon, Meta, and Google—using top tech and ML for relevance, simplifying demand scaling while de-risking media investment, and expanding inventory without harming organic metrics.
A purpose-built, ML-driven partner like Moloco can maximize first-party data predictive power, enabling RMNs to control their ecosystem and unlock sustainable growth.