I don't understand the outrage here. The App Store is private property. The owner of that property (Apple) has the right to use that property as they see fit. Developers are also free to agree to the terms of the App Store or not. The purchasers of Apple products are also free to buy things from the App Store if they choose to.
How is this unfair, evil, or wrong I don't understand. Unfashionable, yes. Wrong or unfair, no.
They can keep it up until they are ruled to be a monopoly - I'm not sure that will happen to them but when it does then they can't act the way they do now without consequences.
I think it'd be a little different if they didn't lock down the device so that their App Store is the only (supported/permitted) way to install applications. If it was only "you sell through us, you pay", that'd be one thing; as it stands, it's "you want to run on these devices that our customers bought, paid for, and own, you pay us too".
How is this unfair, evil, or wrong I don't understand. Unfashionable, yes. Wrong or unfair, no.