Handshakes, Seperation, and Conformity

Over the summer I attended a business and entrepeneur camp type of deal at Stanford University in California. I did learn a ton about of business and starting a business, but meeting the kids at the camp was even more fun. The teens here were much more mature then you find at a typical highschool (which I think was due to the high entrance fee). The first two days was good because it was everyone saying "Hello, I'm John. Nice to meet you!" Followed by a handshake. The amount of weak handshakes I got was staggering. It made me think that no matter how confident you are, a weak handshake can totally destroy that swagger you are giving off.
I noticed a interest start to form between two of my group members. (really the whole group did.. we all joked about how they were always together). It wasn't all positive talk. None of us liked this guy because he was a too cool for school boarding school kid who really flaunted his money and thought he was better then us. We devised a plan for the bus ride to Yahoo Inc. One of the loudest talkers in the group was going to distract him about our business plan after the girl had gotten on the bus, and we were going to surround her so he wouldn't be able to sit by her. The plan worked perfectly and he sat alone near the front of the bus. Later on in the week she realized our group dislike for this guy she had been always walking with and chatting to. She started to seperate herself from him, such as saying things like "Oh look whose coming to sit by us" at lunch and "Why does he always come and walk by me?"
I'm not going to try to hint what was happening like in those essays we've been reading. She was changing her own thoughts to the same as the majority of the people around her.
Why do the maturest of kids I've ever met still fall into the catagory of immature? Because I don't think this is a matter of maturity. I am sure there are adults whom have done the exact same thing. I once saw a scientific experiment by Solomon Asch which had 5 people in a room and they would show them a picture. The picture had a line on it with 3 lines next to it, one the same length, and the other two obviously a different length. But the part that made it interesting was that 4 of the 5 people were not actually in the experiment, but were actors that on purpose gave the wrong answer. At least 25% of all the people that were tested gave at least one wrong answer because the rest of the people were.
So why do these people do this? Too be honest I do not know. I'm no psychologist, I just think that they think they might just hurt the other persons hand.