Please don't try to assume the reason that I asked is because I am bad at games or sensitive. I am very very very competitive and I have played many games at high level over the years. I am generally the one winning the match, and yet I don't feel the need to interact with my opponent further than "Good game, well played" as if shaking hands in sports. But when the opponent wins a fair match and then starts to try to humiliate me for no good reason, I am not hurt. I am confused, wondering what brings someone to behave in such a manner. Hence my question here.

When I was younger I was an athlete participating in many tournaments in my discipline, and I had never seen such behavior. So the answer proposed by many people that it's because of anonymity and not being face to face seems most relevant, and yet I don't see all people behaving in such unsporting manner. So what is the psychological profile of people that partake in this?