In this episode of The Middlemen, we sit down with Mark Grether, SVP & GM of PayPal Ads, to explore what happens when a payments company builds an advertising business.

At first glance, “PayPal Ads” sounds like just another media network. But the deeper conversation reveals something more structural: an attempt to build a merchant-first growth layer on top of payments infrastructure.

Mark describes his role as building advertising businesses inside companies that are not advertising-first. Whether at Uber, WPP Xaxis, or now PayPal, the playbook is consistent. First, define a North Star tied to the core business. Then build the advertising product around that goal. Create market awareness. Operationalize and scale.

The key is alignment. Advertising must accelerate the core flywheel, not distract from it. At PayPal, that North Star is branded checkout: more consumers using the PayPal button, more often, with higher basket sizes.

One of the most interesting tensions in the conversation is how budgets actually get unlocked. CMOs may justify spend using ROAS. CFOs, however, care about relative market share. Are we growing faster than competitors? Are we improving our position in the category?

That shift in language reframes how commerce media should be measured and how it earns credibility at the executive level.

Todd raises another important point during the episode: calling it “PayPal Ads” may undersell what’s happening. If advertising is designed to help merchants grow, through customer acquisition, better merchandising, and shared economics, then this is more than an ad network. It becomes a broader merchant growth platform powered by transaction data.

Unlike retailer media networks that operate within a single ecosystem, PayPal sees transactions across merchants, categories, and channels. That creates a unique vantage point: understanding how consumers behave across the market, not just within one storefront.

The broader implication is this: as payments platforms, retailers, and marketplaces build media layers, the real differentiator won’t just be data. It will be incentive design. Who is the system built to serve?

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