I think after quilting a while, giant arrows develop over your head and follow you around, letting people know you are a quilter and will take any fabric off their hands. Same thing happens with yarn if you are a knitter.
We were lucky enough, when we started quilting, to meet 3 ladies (separately) who had cottage industries making quilts and buntings, and they gave us tons of scraps. All we ever had to buy was yardage for backings. And I mean they considered "scraps" anything up to about 2 yards.
I still have some of it left.