Is MBA about giving fundas?

My wife complained to me yesterday that ever since I have come back from my MBA school, I have started giving fundas to everyone. She mentioned while listening to a conversation with my friend over phone, that every statement he made, I had an opinion on it. I classified it as either good or bad, useful or useless, interesting or bad, so on and so forth. Her argument was that may be the other person just made a statement and didn't expect that statement to be evaluated on my scale.I didn't agree to her initially but it forced me to think. So, what is it? Is it that MBA helps you to think through everything and helps you make quick decisions or is it that just get so much accustomed to giving your opinion as a part of "evaluated" class participation while discussing the case studies? Whatever it is, I think I need to take this feedback and work on it.