Fred is one of the book's most outspokenly cynical characters. Like Floyd Ferris, he doesn't mind cutting through the crap and admitting to what's really going on, which people like James and Eugene Lawson find horrible and upsetting. Fred sums himself and his role in the world up quite nicely here:
"I'm a racketeer – but I know it and my boys know it, and they know that I'll pay off. Not out of the kindness of my heart, either, and not a cent more than I can get away with.... Sure it makes me sick sometimes, it makes me sick right now, but it's not me who's built this kind of world – you did – so I'm playing the game as you've set it up and I'm going to play it for as long as it lasts – which isn't going to be long for any of us." (220.127.116.11)
Unlike Dr. Ferris, Fred is very much a pragmatist. He isn't ideological at all; he's just trying to survive in whatever system happens to be in power. While Ferris quotes party lines and rhetoric (however ironically) Kinnan makes sarcastic and cutting comments that blast meaningless rhetoric to smithereens and send people like James into hysterics.
"Say," asked Kinnan, "how is the emergency to end if everything is to stand still?"
"Don't be theoretical," said Mouch impatiently. (18.104.22.168-8)
Fred Kinnan has some of the funniest dialogue in the book. Granted, it's dark humor, but it's still funny.
Fred is also the first to concede something akin to defeat to John Galt, pragmatist that he is. Overall, Fred Kinnan really stands out among the looters for being willing to say what many of them are thinking: they're in it for the power, and they're all doomed.