I was reading some comments on Slashdot regarding the Spotify vs Apple story, and some where saying "Spotify just wants to sell music subscriptions while asking to be hosted for free on Apple's app store. If they don't like paying 30% they can just make their own device and app store".

Yeah, as if you can build an ecosystem as big as Apple from scratch just on the premise of selling music and nothing else. Some people are just out of touch with reality. Microsoft, with far more resources, tried with Windows Phone and it failed.