What does this construction mean and what are it's limits? Why isn't it Taqueria de la Michoacana? Is this a common way of naming things?
More or less as MikeWats mentioned, stores are often named by store type (zapatería, bar, cafetería, taquería, etc) and then given a juxtaposed name (that is, placed without a preposition). It's common anywhere not just in Mexico but all over the Spanish-speaking world, although less so with newer more commercial/(inter)national places that go with a single brand name.