Have you submitted an app to the app store? Have you dealt with their reviewers? The stupidity of these reviewers is maddening. I'm certain I do not want a phone call with them, even though they are extorting $99/year from me.
Apple has been the vanguard of selling software for years. People don't buy desktop software anymore, and it wasn't all that successful to begin with. They do buy software on phones, though, and Apple enables an ecosystem that might not otherwise exist. It's not clear to me that Google needs paid apps. They were happy with ads before that.