I am a Yankees fan, not a hard core one, but a fan.
My buddies and I travel to 1 Major league Ballpark every year to see the Yankees play. In my case it is more of an excuse to party than see baseball.
We have been to Baltimore, Toronto, Cleveland, Chicago and Boston.
By far - The Redsox fans were the worst. We almost got into a serious fight with a BUNCH of dudes just for walking along the street with Yankees hats on. In all the other cities, the taunting was generally good natured.
Redsox fans have so much hate built up because their team can't win a fucking world championship, while the Yankees are the greatest team in the history of professional sports.
You are always hated when you are the best
That's why so much of the world hates the United States.
Just a fact of life....