Here's a pairing worth sitting with. On today's earnings calendar, two consumer-staples giants — Constellation Brands and General Mills — reported flat-to-shrinking volumes and leaned on price to grow. Meanwhile, the platforms those same brands buy ads from are compounding. Retail media is now the fastest-growing profit pool in commerce, and this summer the action moved decisively off the shelf and onto the delivery app.
The scale is no longer a rounding error. DoorDash, Uber Eats and Instacart together generate more than $4 billion in annualized advertising revenue, industry estimates hold — with Instacart's advertising-and-other line alone reaching $286 million in a single quarter. For a decade the retail-media conversation was effectively "Amazon, then Walmart, then everyone else." The delivery and quick-commerce platforms have quietly become the "everyone else" that matters.
The product news this summer shows what they're actually selling. DoorDash unified DoorDash, Wolt and Deliveroo into a single Global Commerce Media Platform spanning more than 400,000 advertisers, launching a premium homepage format called Spotlight, an offsite ad engine (Symbiosys), and — the tell — a clean-room measurement partnership with LiveRamp. Instacart, for its part, debuted a clean-room offering of its own, Data Hub, and extended its self-service ad tools to retail partners. Best Buy, Instacart and DoorDash are all expanding their retail-media offerings to win over reluctant advertisers.
Notice the common thread: clean rooms. The land grab of 2024–25 was about inventory — how many sponsored slots a platform could sell in search and browse. The 2026 fight is about measurement — proving to a CPG that an ad served inside a grocery app actually drove a purchase, without either side handing over raw customer data. Whoever wins the credibility war on attribution wins the budgets, because the brands are getting far more disciplined about where ad dollars go. That's the point Digiday made about smaller networks stepping out of Amazon and Walmart's shadow: they can't win on reach, so they're competing on closed-loop proof.
Which brings the story back to today's earnings. When a Constellation or a General Mills can't move more units, the lever it can still pull is defending its share of the cart it already has — and increasingly that means buying placement and promotion inside the exact apps where the purchase decision now happens. Stalled volume and booming retail media aren't two stories; they're the same one. The suppliers are funneling a rising share of trade spend into the platforms' ad systems precisely because organic demand isn't doing the work anymore.
For retailers, the read-through is strategic. A grocery-pickup lane or a delivery integration isn't just a fulfillment cost center — it's ad inventory, and the margin on that inventory dwarfs the margin on the groceries themselves. The chains that treat their apps as media businesses, and can offer advertisers real clean-room measurement, will find themselves with the most durable profit stream in a year when moving actual product keeps getting harder.