I'm not sure how surprised Americans would be to learn that there are so many "centers of Europe". After all, we all know that Colorado is in "the west", Texas in the "southwest", and, clearly, "the South" is located in the geographical southeast :D

These American peculiarities are funny too, but they are mostly historical, and from that perspective have reasonable explanation. In turn "we are not Eastern, but Central" is relatively recent PR-born madness. Somebody decided that EE often associates with questionable things like alcohol consumption somehow, so the solution is to separate yourself from other drinkers by claiming being completely different "Central" kind. Nobody stops drinking meanwhile, because why would you? I simplify the story, of course, but the logic is exactly like that.