I've always thought Palm used patches as a nice alpha/beta sandbox for the public. They let the public play in the sandbox. They can be creative and even build things to play with. All while Palm is watching to determine what their users desire. Once Palm sees something they think would be widely accepted on a large scale they incorporate it into an official release. A good example of this is LED blink notifications. This is a nice arrangement since it saves Palm time, development costs, and insures new functionality has already been accepted by a large group in the community. It's a win/win for everyone.
Making patches "official" would just create issues Palm doesn't need and probably doesn't want. If we didn't have such a great community working on patches and other endeavors Palm might consider stepping in. I for one like the current arrangement.