I've played poker in real life and I've played Poker Night at the Inventory (but not Poker Night 2).
I have the feeling that the Poker Night engine manipulates the deck to give players a more interesting game experience. I'll come right out and admit that I base this entirely on subjective evidence, but it seems like when I'm betting big and hoping for a miracle to come along on the last card, I'm more likely to get it in Poker Night than I am to get it with a real deck of cards.
Is this just luck or do the Poker Night games cheat to make things more dramatic?