I prefer plastic as I have one of the trash cans that they fit in perfectly, thus saving on trash can liners. I take the trash out more often now, instead of letting it sit and possibly smell. I would not use the paper bags from a grocery store for anything that my food (fresh baked) touches, as you never know what may have touched that bag! Just think how many times that "item" you bought has been touched and put into that bag (not to mention the roaches) by someone, that I am sure did not wash his hands every time he got into something!! EEEwwww! I know people that use newspaper for fresh baked cookies to cool on......yuck!