Admittedly, I also wondered about this. I'm taking Patreon at their word (for now), but I would welcome Apple making some kind of statement indicating that Patreon is allowed to disable payments in the app.

And if it is true that they're not allowed to disable payments, I would also love to know what's special about Amazon, Netflix, and Spotify (other than their size) that would allow them to "get away" with the same behavior.