Reading through the actual study, there were 752 fans surveyed, but 290 were fans of one team, and 27 were for teams other than the 10 teams they were focusing

Reading through the actual study, there were 752 fans surveyed, but 290 were fans of one team, and 27 were for teams other than the 10 teams they were focusing on, so really the analysis was a survey of 435 people. Also, the measure of affinity was answering a hypothetical question (a version of the Trolley Dilemma, except the person being asked would have to sacrifice himself/herself). So I'm a bit skeptical it's as simple as the study makes it out to be. Anecdotally, it seems like it should be more complicated too. As a New York Yankees fan who was in Massachusetts when the Boston Red Sox won their first World Series (Major League Baseball) in 80+ years, it seems winning was a pretty big bonding moment for Red Sox fans. I think affinity must also be different depending on the region. If you go to Boston, there are signs everywhere for the Red Sox and Patriots. In Seattle, everything is all about the Seahawks. In the New York area, we have multiple teams in the major pro sports, so sport-team-affinity and location-affinity are necessarily more loosely coupled here.