This is so tiresome. The 30% is a service charge. It covers hosting, distribution and credit card processing to name but a few things. Before the AppStore, entities such as handango we're charging more than double as a percentage. It's not an arbitrary figure that you seem to think they plucked from their collective asses when instigating the store. So please. Drop the fucking trite meme. It's vapid.
I didn't question the fairness or value of that commission and frankly, its irrelevant to the point at hand. If they officially allowed bitcoin on the AppleMarket, there's no telling how many vendors would offer it for an absurdly bigger profit margin.
Being practical, this means that theres space for a solution to charge intermediary commission and let apple have its piece of the pie.
Bitcoin is a risk on the controlled environment they have.