I've played live a couple of times, and I'm always a lot more wary when at the tables, cautious of other peoples attitudes.
I remember my first time at a live tournament, I had one fella on my table that was calling for the rule book at least every 4 hands. Apparently this was his game to get rid of players who were new to the live game scene and to make his presence known. It was even sweeter knocking him out though with a straight over two pair.