There's a bunch of guys I play with regularly but they are pretty much just tennis friends. We never see other outside a tennis setting. There's one guy I have been playing with for more than a year and I don't even know what is his occupation. We sit around at tournaments and almost always talk tennis during the down time between matches-pros, upcoming opponents, stringing racquets, ect. My wife asks me about them and I feel that I barely even know them even though I see them probably more than my "real friends" Is this pretty common?