Purchase history would just be what apple knows, not your general purchase history.

If you use Apple Pay, for instance, they’re the middleman and have to know, and anything you buy on the App Store.

A legitimate reason to share that is a budgeting app. Facebook is taking advantage of that, obviously, but in this instance, I see no fault from apple, here, there’s reason to allow an app to get that, so an app can request it, and we can deny it by not getting that app, so fuck Facebook, I’m not downloading it.

Dunno for sure, I feel the same way as you, but I think it’s more about "I refuse to use the app you intended me to be forced to by killing [favorite 3rd party app].

If combined with an adblocker they don’t get your ad revenue but they do still get to add you to the tally of “active users”, so I still feel abandoning ship altogether is best practice.