i sell mine, i have only kept 1 quilt in 8 years of quilting and thats only because it was a gift i gave to DH.
i can't imagine keeping everything, the costs of fabric, batting, notions, sewing machine, long arm is so expensive and to never get any of that money back would make buying very difficult.
i have no problem buying things for quilting because its my business (my only source of income) and i'll make my money back plus some.