Leesa, I'm so glad you asked this question. I have always wondered about the same thing. Another thing that puzzles me is leaving the paper in. Someone posted earlier a neat string quilt done on phone book pages. I was embarrassed to ask it she let the paper in. Wouldn't that be uncomfortable? I do know from history that women did newpaper piecing for those in the war. This was to keep them warm. I just can't imagine washing a quilt that has paper foundations.