Although some quilters used scraps from clothing in their quilts others bought fabric specifically for the quilts they made. Other times quilts were made with a combination of both. Fawn Valentine points out in her book, West Virginia Quilts and Quiltmakers, "Although imaginative lore spinners claim that patchwork quilts themselves are made with worn-out cloth it was typically the good pieces (not the worn) that were cut and stitched into patchwork. It would be counter-productive to spend time sewing fabric that was already worn out." p194 Of course scraps left over after making garments were used in scrap quilts much as we use left over scraps from our quilting projects today when we want a scrappy look.
The frugality theory also implies that quilt making was a necessary drudgery. Instead we find that most women enjoyed the creativity involved in making a quilt whether with new fabric or scraps. Although quick and simple quilts were made for everyday use many quilts were far too intricate in the piecing and quilting to have been made just for necessity.
This is not to say that women never used scraps to make a quilt in order to save money or to get by because they had no money to spend on fabric. Women did use scraps left over from making clothing. They also made quilts using feedsacks during the years they were available. But the frugal quilter myth implies that most if not all quilting was done out of need to make something frugally.