Xfinity NOW keep getting paper bill for $0.00

I have Xfinity NOW internet only and Xfinity NOW mobile. Every month I have been getting a Paper bill in the mail for $0.00 and this seems like a waste of paper. Can I go paperless even though this is a prepaid service? I believe the mobile and internet are seperate accounts since I get seperate emails stating that my account is good to good for the month, so why the paper bill? all it has is my account number and your bill at a glance which states Previous balance $0.00/Payments $0.00/Balance forward $0.00 but does not state which services they are.