I can't speak for anyone else, but I'd be wicked upset if I couldn't buy 3½ or 4½ yards if I wanted to just because the 'unit' was set at one yard instead of a half yard. I find it convenient, not deceptive at all.
At least a half yard of fabric is still a half yard...unlike a half gallon of ice cream or a gallon of paint. Pretty soon a dozen eggs are only going to be 10.