No one I know watches tennis like I do so not really. The only thing that is affected is that people think I'm certifiably insane because I stay up to watch matches at 3 a.m.
I definitely don't get into fights over team sports, it's more just good natured trash-talking. It's fun to make fun of each other when the other team loses. The best is the New York-Philadelphia rivalries like the Mets-Phillies or Giants-Eagles.