That's true, bear. When I was growing up we had a favorite sit on the the floor in front of the TV quilt made of samples of velveteen upholstery fabrics in large rectangles. It was a tied quilt and much used. When it was getting lumpy from the "batt" starting to come apart and shift, my mom decided to take it apart and repair it. When she took the binding off, there was an old wool blanket inside.
My mother was raised in a rural area of the midwest in the twenties and said that they always sandwiched old quilts in new fabric to make new quilts. They also cut up the boys old wool trousers in strips to use for log cabin type quilts as the wool was heavy and warm (no central heat in those old farm houses!) and there was no money to buy new batting.