In case of an app, what is the "product" you are buying? Because according to Apple, they add a lot of "value" by ensuring the software is safe, performant, etc etc. Am I not buying "a safe, checked app"? Or am I buying an app and then separately pay Apple for an added service of "checking the app for safety" etc etc. I'd very much presume the first.
But if its separate, "an app" can be rather ambigous. For a one-time-purchase game, its clear. But many apps are really a service or even more that happen to have "an app" as one of the ways to interact with the service: Netflix, Uber, protonmail, Vinted (or ebay), etc etc: the app isn't the thing I buy. It's a wrapper around a service. Or even just one of the portals through which I can buy stuff. Point being: It's not simple, so your answers don't fit the analogy of "wallmart".