There are regions (or ‘sub-regions’, since Europe is one of the regions; see also below) there? I’ve never heard anything like it.
You could (or are supposed to) also specify a country in your bnet profile, and it might affect some offers in the shop (as for Russia in particular, since some people have mentioned it, I think rune$tones aren’t offered in the in-game shop for players with this country in their profile, but that’s apparently it; previously, some bugs (?) related to the shop, affecting Russian players, were reported, but these are bygones now anyway), but I don’t think it’s got anything to do with the problem in question.
For me personally, for example, the shop has been permanently closed since the big patch.
Truly?
I’ve always thought there are three: Europe, Americas and Asia. You can actually choose one in the Bnet client when you launch the game.