One thing I've observed about playing mafia is that you find out secrets about others that you'd probably never know about in real life.
Those who fake investigator roles greatly astound me as they are able to deceive others. As I play mafia, I wish that I would never know these in real life, and, hopefully, have not already known them.
PS: I, rarely, if ever, CC cop. If I claim cop, most of the time, I really am cop.
Games: Epic win as fool: http://www.epicmafia.com/game/514476