I actually have two Facebook accounts. It happened because Facebook decided that I was a hacker and blocked my other account from me, and I couldn't request a password change because when I did they never sent me a code :S Took me a month to get it back. In the meantime I made a new one. Some people added me that I didn't have on my original one, so I decided to keep it :S Kinda silly I know but I use my new one as a business one. That way if people I work with want to add me, they can on there. I don't go on that much there so it's not a big deal, they can't see my personal stuff :) Not that I post anything I would regret, but my original one is not in my real name :)
I don't use it for cheating or anything, just keeping my image clean and giving me freedom to be me :D
Yes. He plays games on Facebook. So he has one account that's for his real life contacts. The other is for his game account... he'll add random people and that makes the game better/easier. He doesn't want random people participating in the game mixing with his actual friends/associates.