HA! I think this falls into the sofa is a couch catagory! Comforter is just another word for the same thing.
A quilt is the process of joining layers of fabric together through stiching, right? Well a comforter is the same thing! just plusher, thicker, or with less stitching.
I say a thick quilt is a comforter. I just see it as a tomAto, tomato sort of thing!!