I have not used the end rolls for paper piecing. I don't have the patience to cut them up. Our newspaper goes through a lot of paper I guess. They won't give you much if you get them though. I was able to get 3 since two were going to the school.
I would much rather get the precut pages to go through the printer. Having said that, my next paper piecing project will be freezer paper so I don't have to rip out paper ;)