Wait, am I understanding correctly that Apple and Google actually charge developers money to produce the content that Apple and Google monetize on their app stores?
They charge to have access to the dev tools and the right to publish apps. There are real costs to doing this right and I believe most developers are happy to pay.
That hasn’t been true since XCode 7. You can side load apps onto your own devices from XCode with a free developer account, you only have to pay the fee to submit apps to the App Store.