I will buy a fat qtr collection because I love it. Then will make some scrappy quilt out of it. I always add other fabrics to stretch it from my fat qtr stash and/or colored solids. There is always some neutral muslin added in there some where too. I find if I make a quilt out of just the collection, it is too much "the same". Bonnie Hunter use to go with random scraps divided into lights and darks....but lately (like in her recent mystery quilt), she is making her own "collections" out of color palettes specified by paint chips. So, scrappy is getting more "structured" in the quilt world.