I don't know what Apple is thinking, but it seems more likely they want as many and as diverse a field of apps as they can get. If some small company comes up

I don't know what Apple is thinking, but it seems more likely they want as many and as diverse a field of apps as they can get. If some small company comes up with a "killer app," they can buy it and make it part of their brand. This would be a strategy by which they effectively out-source the dev risks of killer apps. I don't know if that is what Apple is thinking, but that is what I would do.