What's your golf pet peeve?

I hate unsolicited swing tips. Now, if I am playing with golfers who I know to be leagues better than me, I will definitely accept any advice they offer, but in most cases, its golfers who are either on the same level as me, or worse than me that try to give me advice.

Played in a 4 man scramble with a friend and his buddies this weekend. I've played with one of his friends before, but not the 4th. For the first 5 holes, we only used my and my friends shots and were 3 under. Come hole 6 and the 4th guy (who is not very good and claims he hasn't played in a while) starts giving me putting tips and tries to get me to change my grip. I told him that I'm glad it works for him but I will stick with what I've got working. He took it personally and asked why I don't take advice in golf. I reiterated that I was fine with my current putter stroke.

If the guys was actually sinking putts and appeared to be good at it, I would have considered his tips. However, we didn't use any of his shots at all that day, so I'll just keep doing what I'm doing.