Thank you, Laofan. I couldn't have said it better myself.
Merriam Webster Dictionary defines "coupe":
"a 2-door automobile often seating only two persons
also : one with a tight-spaced rear seat"
It seems to be a desperate attempt on the part of manufacturers to be exotic in their naming of models. Nowadays we can see it elsewhere with other terms like, "fastback". And, I don't think the blame lies only with Chinese manufacturers.