Annoying

So, I just want to put this situation out there....What if you were sitting at the lunch table at school and you are the new kid, obviously trying to meet people. You become involved in conversation and begin to notice that everything you say, a certain person has to constantly tell you what and how they would have handled the situation and put in their two cents on every word you speak.

For some reason, this absolutely drives me nuts. Let me list the reasons.

1) I don't know you from Adam.
2) Are you Cliff Claven from Cheers and know EVERYTHING?
3) I personally don't really care, nor asked you your opinion and I probably never will.

For some reason, this really bothers me when people act like this. I don't know if it's because I already know everything or because they have no social skills... Im leaning towards the no social skills.