In some cases, not all, you spend the game having the other team talk **** and basically show you no respect and then you are expected to shake hands or you're a bad sport?
I think that some old school guys would question today's professional athletes shooting the bull and hugging before and after games. If that is how you display your level of competitiveness then okay, but if you want to go out and crush your opponent and not be their buddy then that should be okay also.
I can guarantee you that Michael Jordan wasn't going out for steaks with guys from the other team after Game 3 of the Finals.
The handshake line is overrated, with the exception of 5 year olds soccer games and the NHL Playoffs.