Wouldn't that count things like ordering coffee in an app? I spend perhaps far too much money on coffee ordered through my iPhone. That's an in-app purchase, right?
I would guess in this case it's just normal merchant fees (no larger than 5%). But I don't know how this all breaks down. It's not like they take 30% when you use Apple Pay at a store. Ordering coffee in an app seems more like an extension of that.