Interesting. I know absolutely nothing about the ins and outs of showing anything, but surely if the quilt has won awards before or been "shown" via shows or electronic/print media before; it should be excluded from competition. Maybe well-knowns or professionals with known quilts could exhibit (therefore "advertise" themselves, their patterns and their previously awarded works) but be excluded from the judging. They get their kudos, but amateurs and professionals who have previously unawarded works get a fair chance of an award.
As some others have mentioned, I think it perfectly reasonable to mention the name/company of anyone who contributes to the work in question. There's many a quilter who can turn an average quilt top into a stunner, purely by picking the right design and thread to bring out it's best.