Having a walled garden is fine. I use iPhone and apple products from day 1. That said, charging 30% of subscription in the App Store seems ridiculously high if

Having a walled garden is fine. I use iPhone and apple products from day 1. That said, charging 30% of subscription in the App Store seems ridiculously high if you put yourself in the 3rd party vendor place. For comparison, Amazon charges 15%. AWS marketplace charges <10%.