I know what you mean its just not really the same thing here.. if every store had their own 'app store' then whats the point of an app store anyway? Again as someone who has lived through a world before app stores, as long as the app store is fair its really the way to go.
I have yet to see a "the app store" that is fair, and I have a rather hard time imagining one even existing in the real world. As long as they have exclusion policies, I want as many different "app stores" competing with each other as possible.
As long as the app stores aren't walled gardens it doesn't matter if there are a bunch - likely they'll all have 95% of the apps. It's only a problem when every second app is exclusive to a specific store.