Facebook's effect on society is still being studied, the jury is still out. It may very well be more damaging than doing good. Just because people are paying for something doesn't mean its doing anything good. Tobacco is a good example.
Like it or not, there is also a huge amount of legitimate interactions on facebook.
My dad didn't use internet forums before.. now he's on facebook groups about wood working -- I doubt the projects and reviews people in those groups share are fake news :)
Fact is: without facebook my dad probably wouldn't participate in any online community.
