Actually there's a massive difference. I'm not forced to buy software only from Dell just because I bought a Dell computer, or only from Verizon just because Verizon provides my Internet access. Or join the "HP Developer Program" and download the "HP SDK" just so I can sell my Windows app through the "HP App store" to someone using an HP laptop.
If all the app stores were just stores competing on a level playing field it would be a good thing, but they're obviously not. Most of these are not real "stores", they are schemes for extorting money from users and developers by removing (not enhancing) their ability to choose.
