I haven't tried to crack Steam games, but I don't have any difficulty pirating Steam exclusive releases.

Admittedly the few times I did pirate Steam games it was about price (as in I didn't want to commit the money while not knowing anything about the game, some really great titles like Super Meat Boy are a bit more expensive than you'd expect, but are absolutely worth it if you happen to like the genre). Steam is almost infinitely preferable to a pirate torrent, lacking only a sane download manager. But otherwise I consistently get faster downloads with less annoyance and I get nice integration with multiplayer and my friends' gaming.