I went back to uni at age 30. I was much more conscious about how people befriend each other. I don't understand it, to be frank. But I used to take it for granted.

I see certain people meet up and I have no clue why these specific people become more friendly with each other. Why do they pick each other? Of course it happens naturally and they probably don't know why it happened. But for more than 60% of the people I see are close in class, I don't get why.

I don't see much of what you call 'ego boost' going on. Not sure exactly what you mean with that. But I may be oblivious to it anyway.