In theory it should work
It could actually make for a way better user experience if ou local operators make their own app stores, imagine apps like google maps, or foursquare etc. that is specifically designed for us South-Africans.
They would have a lot more features that we can actually use, i hate being told something is not available in my area..., and they can be made to tailor for the conditions that most of us are stuck with here.
Wouldn't it be great if vodacom or mtn could give you a VOIP app or service where you can make free calls as long as you use their data network? Or if there is a gps or maps app that would actually give you live traffic feeds.
Plus it would give rookie app developers in SA an easier way to submit their work and make money...
So ja, again in theory, there are a lot ways this could be really helpfull, but lets face it in SA the apps would crash every now and then because they weren't checked properly before being made available, etc. etc.
Our operators usually have a way of taking something great and ****ing it up