my stash has grown modestly... I started quilting from scratch 5 years ago and I have been pretty disciplined with sticking to my original plan of only buying with a project in mind. Like Gramajo and GEMRM posted, my scraps have grown from having leftover pieces from borders, backing and unused cuts... which I have now organized into 3 totes labeled crumbs, strips and larger scrap pieces.
I am often envious of members who have larger stashes to shop from... but until I get my sewing room built over our garage I'll have to stick to my plan.