I get that but it does not exactly match my pet peeve. I am not put off by those kinds of fanships. My opinion is based on fan preference
within each particular sport, whether it is at the college or pro level (or even high school). For example:
College Basketball
Duke fan only? Yes! Duke
and Clemson fan? No.
College Baseball
Texas fan only? Yes! Texas
and Vanderbilt fan? No.
NHL
Boston fan only? Yes! Boston
and Chicago fan? No.
NFL
Dallas fan only? Yes! Dallas
and Seattle fan? No.
I love it whenever someone says they are fans of two different teams that play each other. You ask, "Who are you rooting for?" They say, "BOTH!" It is like sitting beside someone at a football game and hearing them yell in the same breath, "GO DEFENSE! GO OFFENSE!" There is no unwavering loyalty to any one team. Those fans lean in whatever direction the wind blows. May as well root for the referees too.
Players come from lots of different loyalties for teams growing up. Nothing wrong with it. Players get drafted rarely by their favorite team and should not be questioned about a lifelong loyalty to another team. I am cool with those situations. It is those with two, three or more favorite teams in the same sport who make me shake my head.
/mini-rant