That is a tradition of Native North Americans, it's because of it's use, not to put down the art - even the most intricate combos of patch and applique with embroidery + you name it are 'blankets' - I think i't kind of folksy and nice, once you get used to it!
Maurene, Montreal
PS - one of the best quilt shops around Montreal is on the Mohawk reservation here - the ladies that run it take a super, personal interest in everybody's 'blanket' projects! I gues I've gotten a bit partial to it!!