I have recycled used clothing into quilt fabric for years. I shop yard sales and rummage sales as well as thrift shops. One church generally has a bag sale shortly before closing time of their rummage sale. One can purchase a brown grocery bag for a dollar and take home as much as he or she can stuff into the bag. At their last sale, I purchased 2 bags and stuffed them with mostly 100% cotton extra extra large mens shirts. I may not live to use up all that fabric.