What Apple is going is just obnoxious and as clear a case of anti-trust as has ever been.
30% of revenue for no services offered, just because they can, is the definition of extortion. The only thing stopping them from asking 30% off of your Amazon orders placed via Safari is because the consumer has a choice of another browser for free. Otherwise these high priests of design and aesthetics would make the shirt on your back cost 30% more.
Your app can't even tell the consumer that they can pay outside and avoid paying the Apple tax infinitely AFTER paying for their really expensive device. This is keeping the consumer in the dark to exploit them.
This isn't capitalism. This is monopoly abuse.