But how does that help end-users? They would still need to know that they need to use different store etc. It's a pain. At least Android allows (relatively) easy side-loading APK's for the most critical situations, but for iOS that would be a disaster (not sure if Apple's App Store has a way to delete/cancel/pull-back faulty release though).

Honestly this is really not a solution for anyone making a living off apps, or working on apps in a professional setting. You simply reach much fewer people and certainly a different audience too.