Put it this way: they don't care about what the developers have to say about their platform or their policies and they assume that whatever minority of developers has left their platform will be replaced by an army of new ones. I mean, how many people have actually dropped their development for the iPhone/iPad? Have you noticed it?
out of my friends (who develop for the iPhone)? One or two.
Most are still staying onboard (maybe... 25 or so).
Don't forget this is the internet; like most things the disgruntled developers will be the most vocal. That doesn't necessarily make them a majority - or even a large minority.
Obviously they only do so to benefit themselves, but it's quite clear from their actions that Apple does care about developers.