Until publishers decide to launch their own app store and remove games from the app store, forcing me to create accounts and store payment details with them.
Then, poeple like me who explicitly purchased apple devices because this is a feature, are forced to have a "choice" between install the app and the store of their proviser, or no app. That's a lose in my book.
App Store transaction fees amortize the costs of development/operations of not just the store itself but the OS it all runs on. If you pay 99¢ for an app that covers re-downloads and multiple devices in perpetuity. All running on a global CDN with exceptional uptime.
Apple doesn't charge users a dime for new iOS upgrades over years of the life of the device. Even years old devices get the latest software features of new iOS versions. Supporting old devices has a non-zero development cost.
Considering how Apple makes almost 50% hardware margins on every iPhone sold, I think they make plenty enough to continue software support off the initial hardware sale alone.