As an European, I still prefer the freedom to have alternate App stores.
Yet, I still don’t see a reason why they don’t provide the same app to all customers since it’s allowed by Apple, aside from greed or something like that.
Either way, let these developers enjoy their small time of fame, because as soon as RetroArch becames available, a lot of these emulators will be left in the dust ¯_(ツ)_/¯