Yeah, good point. The question is why? Surely in Apple's case they've done the sums and worked out that such restrictions are profitable in the long run. Looking at their financial results it looks like they are right....should be more anti any big company putting restrictions on.
But on the other hand there are some big companies that are totally open... Nokia's Symbian for example.
So why does the market reward restrictions, locked down stuff? I know I tend not to buy stuff with artificial locks. A bought an audio book from iTunes ones - it was locked and I couldn't play it on my SanDisk Sansa MP3 player. It was the last thing I bought from iTunes!