# Retail media networks scramble for incrementality proof as advertisers demand real impact data

*Brands now require attribution models showing sales lift beyond what would have happened anyway.*

By **Jenny Huang Goodman MPA MSc MHSA, Principal** — The Stash Edge, Hako Shikin LLC.
Published 2026-08-05.

Canonical: https://www.pops4.com/stash/articles/modern-retail-retail-media-networks-2026-08-05t09-6
Subject: Modern Retail / Retail Media Networks
Tags: retail media, incrementality, attribution, Amazon ads, conversion tracking, media spend

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Retail media networks are facing mounting pressure to prove their advertising actually drives new sales, according to Modern Retail's coverage of advertiser demands for incrementality measurement. The platforms — advertising networks run by retailers like Amazon, Walmart, and Target — generated an estimated **$55 billion** in U.S. ad spend in 2024, but brands are now questioning whether those dollars deliver true incremental growth or simply capture shoppers who would have purchased anyway.

The issue centers on attribution. Most retail media platforms report last-click conversions: a customer saw an ad, clicked, and bought. But that metric doesn't answer whether the ad caused the sale or merely touched a buyer already en route to checkout. According to Modern Retail, advertisers are now demanding incrementality studies — controlled tests comparing sales with and without ad exposure — to separate actual lift from credit-claiming.

The mechanism matters because retail media sits at the bottom of the funnel. A shopper searching "paper towels" on a retailer's site is already in buying mode. An ad for Bounty in that moment may convert, but the purchaser might have selected Bounty regardless. Without incrementality proof, the advertiser pays for influence it never exerted. The World Cup presented a test case: Modern Retail noted the event offered retail media platforms a chance to demonstrate impact at scale, where attribution could be measured against baseline sales periods and control groups.

For a physical product brand, the incrementality gap creates both risk and opportunity. The risk: wasting budget on retail media placements that earn credit without earning sales. The opportunity: competitors who ignore incrementality will overspend on low-impact placements, leaving budget and mental space for brands that allocate more precisely.

The steal starts with defining your own incrementality baseline before the retailer does it for you. Run a simple holdout test: pick two comparable weeks and run retail media ads in one, not the other. Track total sales (not just attributed sales) for your product in both periods. The difference, adjusted for seasonality, is your rough incremental lift. If lift is under **15%**, your retail media spend is largely paying for sales you'd have captured anyway.

Next, shift spend toward placements with structural incrementality. Prioritize sponsored product ads that appear in competitor search results, not your own branded keywords. A shopper searching your brand name has intent; you're paying to confirm a decision already made. A shopper searching a competitor's name or a generic category term is persuadable. According to retailer ad platform data cited in trade coverage, cross-shopping placements often deliver **2-3x** the incremental lift of own-brand keyword buys, at similar cost per click.

Finally, build incrementality language into your retail media buy. Request weekly sales reports that include total category movement, not just attributed conversions. Ask the network's rep for access to their incrementality measurement tool (most major platforms now offer them, under advertiser pressure). If they can't provide it, allocate a **10-20%** test budget to a competing network that can. The retailer's response to that request tells you whether they're optimizing for your growth or their attribution numbers.

The broader pattern: as retail media matures, the buy becomes less about reach and more about isolating true influence. Brands that measure incrementality now will outspend competitors more efficiently in twelve months, when retailer ad inventory costs rise and attribution skepticism becomes table stakes.

## The takeaway

Demand incrementality proof from retail media platforms and shift spend to competitor keyword placements that capture persuadable shoppers.

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## Publisher

**Hako Shikin LLC** — Virginia Beach, Virginia. Founded 1997. ASI 217876 · DUNS 18-204-6339.
Principal and author: **Jenny Huang Goodman MPA MSc MHSA**.

- Author: https://www.huanggoodman.com/about
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