I imagine it to be a thing in mainland Asia, Africa, South America, but for US America, a geographically large country and third most populated, sandwiched between Canada and Mexico, there are numerous towns that skirt the border, and even outside these towns there's a bit of an international "exoticism" vibe of being able to just go to another country for any reason. Does this sentiment even occur in Europe because the continent is really small and from all the memes I see about "France is three hours away", it seems like every 3rd to 5th town in any part of any country besides Britain (Northern Ireland is in the UK so Ireland might have a more politically charged definition) would qualify as a border town, making the concept a bit moot and nearly meaningless.