I'm guilty of it as well, if forced to choose blindly I'd pick Sony over WMFSENSY. But I'm beggining to wonder, with the recent casualness with which brands lower quality, whether they'll be a generational change and people will start ignoring brands entirely.
I'm starting to change my mind myself. My last Nike shoes weren't even the same size/shape (apparently they make left and right shoes in different countries now). At that point might as well go for the knockoffs.