Note that the ability to use an alternate payment vendor is a separate question from whether Apple can enforce a contract where you agree to the Apple store fee

Note that the ability to use an alternate payment vendor is a separate question from whether Apple can enforce a contract where you agree to the Apple store fee. This question is one of whether apps should be able to direct you to metaphorical Paypal. As a consumer who buys phones for the whole family, I much prefer payment through Apple due to (1) one-stop shop for cancelling all subscriptions, and (2) Apple is much better on privacy.