Many developers don't want to have apple be their gatekeeper for apps. They should be able to have alternatives. Apple's rent seeking behaviour is to take platform development in the cost of the device and again to distribute apps without any alternative.
On the other hand, if Apple's model allows them to better compete with others and create a superior product that people want ... well then, it's ridiculous to mandate they should do business a different way.
I will accept the argument that apple’s gatekeeping is ridiculous, a lot of that is the bizarre prudishness of the US, but saying that apple should not be compensated at a rate that is generally below the market - the majority of apps on the AppStore are freemium from which apple makes nothing, the remainder are mostly only paying a 15% commission. This is vs 30% or so on game consoles, 30% on steam, etc.
Isn't that because Apple doesn't allow for third party repos/stores/etc?
If that changes after all (I'm personally hoping it does), then it would make sense that the new alternative store(s) would have their own overheads (development, running costs, etc) and would have their own fees.
That seems sensible, yeah?
Sure. And who cares? That has nothing at all to do with the App Store fees. :)