By that logic they should ban Paypal, Dwolla, Gyft, Gowallet, Visa, and any other payment app. They clearly haven't, and I'm not sure how Bitcoin apps are any different. The point is they aren't acting rationally.
And that's because those companies have made deals with Apple behind closed doors that your average app developer can't leverage. It's rational in the sense that it serves their interests.
Care to provide evidence of this ? I led the mobile development effort for a very large international bank which was doing peer-peer payments. We didn't make any special deals and were subject to the same conditions as everyone else.
Apple is acting completely rationally. They are being selfish. Bitcoin wallets have a terrible reputation for losing their customer's money and Bitcoin itself still has very unsavoury elements (drugs, money laundering etc) to say the least. Given that the press love a good Apple story you have to ask yourself why take the potential hit to the brand for no benefit ?
For two years, that bitcoin wallet app was available for download from the App Store. Now, suddenly, it's an issue of "reputation"? What a load of crap.