Users and Facebook use each other voluntarily, for their own gain. It's a normal business that anyone can choose to use or not. Both terms users and useds are o

Users and Facebook use each other voluntarily, for their own gain. It's a normal business that anyone can choose to use or not. Both terms users and useds are ok to describe the 2 aspects of the business, and for arguing which aspect weighs more. Users use Facebook first, so overall users is the more proper term.