Which is why I only offered mine to people who PM me so I can decide whether or not I want to do it. I only add people who I have some sort of repertoire with.
My FB is real, but I provide almost zero info about myself so I am not overly concerned. It is also linked to an old-ass email addy, certainly not the one I use for work and other important business.
Even my close RL friends don't know more about me via FB then where I live and some shopped pics.
I make some exceptions for certain forum posters and guild members. But like I said, you really cant get more then a cursory amount of knowledge about me from my FB.