Every app they download is distributed through the app store. If it doesn't fit the app store rules, it simply never materializes, and so no one ever sees it. You only become aware of these limitations once you want to make an app, modify someone else's app, or, like in my example, want to use an app that isn't officially released in your country.
Apple is very good at disguising these limitations such that you don't notice them unless you start actively thinking about iOS development one way or another. In other words, you only become aware of the walls around the walled garden if you try to escape it.
Apple is very good at disguising these limitations such that you don't notice them unless you start actively thinking about iOS development one way or another. In other words, you only become aware of the walls around the walled garden if you try to escape it.