Costco Warehouse = Apple App Store.
Dyson (vacuum vendor) = WidgetApp (digital goods vendor).
Dyson sold in the Costco Warehouse must use Costco as the merchant. WidgetApp sold in the Apple App Store must use iOS IAP merchant of record solution (??).
Costco Warehouse forces use of Visa (or Mastercard - depends on country). Apple iOS IAP does NOT require Apple Pay.
Of course Apple doesn’t buy goods from suppliers before selling them to customers, unlike Costco. And Costco Warehouse is members only, unlike Apple (unless you squint and view iPhone ownership as a membership).