I don't like to waste anything either. I guess it come from parents who grew up in the Depression. I toss mine in a tubbie in the corner and when it is overflowing, I make a scrap quilt. My kids love them because they are the ones to take camping or on a picnic.
You can make sleep mats and use them for stuffing and donate them to an animal shelter. That is the only thing I can think of to add to what has already been suggested.