This is the heart of the problem: if I open a grocery, I pay the landlord a fixed rent, not a cut in my sales. That's because rent is generally seen as a commodity. Apple doesn't want to accept that their App Store infrastructure is a commodity (it's not cool to be a commodity), so they come up with this revenue sharing system. They see themselves as a publisher.

That's nice if you're a small developer, because the alternative is paying a high fixed fee. So what would that fee be? There's 50.000 iOs developers [0] and the app store generates about a billion in revenue (off the top of my hat). That means we're paying Apple about $300 million. That means the fixed price should be $6.000 per year for Apple to earn the same amount (there's probably no sustainable fixed-price point).

Obviously, if they did that, Android would become infinitely more attractive, since they could offer a much cheaper service (no expensive in-house review team).

So here's the dilemma for Apple: 1 - continue with their publisher business model (percentage), maximize for profit at the cost of karma and long term risk of anti-trust lawsuits

2 - dramatically reduce cost (less or more efficient quality control), introduce a fixed fee that developers can still afford ($500?) or subsidize the whole operation more.

3 - keep the current system, but don't force developers to pay you. Sort of an honor system / convenience. That seems to work well for DRM free iTunes music.

[0] http://bit.ly/pyNwCj