For the sake of brevity, the masculine form in this response will apply to both genders of sex. No disrespect is intended.
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I think it makes many here that have been true fans to our team a bit miffed at those that suddenly come out of the woodpile and jump on the bandwagon of the team that's recently won the championship in their collective sport.
But you shouldn't be that surprised about it.
Many studies have been conducted over a period of time regarding the mindset of American people in how they forge allegiances to certain sports teams and it should come as no surprise that the majority of people have time and time again selected the current champion of that particuliar sport. Numbers have varied over the course of years but one thing has always been factually consistent, the more advanced (technologically) media interests expose these collective sports teams to the populace, the higher percentage of "fair weather" fans come onboard. Exposure has always been the key.
Simply speaking, Americans love a winner. This has been something ingrained in all of us since the early days of pre-school, escalating to more higher levels of learning, in particuliar, courses in the areas of history.
Separation between fair weather fans and true fans have a lot to do (and this should be no surprise) with their upbringing in their respective families. Fathers and sons have bonded over the course of years (and generations) by the viewing of a specific sports team. Much like the aspects of Freudianism, the son is eager to please his father as is the father was eager to please his father and so on. This is how the fanship is built up of, oh say, those lovable losers, the Chicago Cubs or the Detroit Lions (as another example of a hard-luck team). Of course this is not always the case as kids can tend to be rebellious in nature and pick the arch-rival of their father's favorite team as an act of independence (or simply as a means to irritate).
But the average fair weather fan will normally not have that particuliar type of exposure growing up and thus will have leeway in deciding which teams they choose to follow. This is not always factual (as there are always exceptions to the rule) but I think that you will find the majority of them have no basis for teams they choose to favor. They will simply revert back to their early days of school when they were taught how America has always been the best and pick their sports team based on that principle. That's why during the 90s, the favorite teams of most fair weathered fans were the Cowboys, Yankees & Lakers. It's like I said earlier, Americans do love their winners.
No foolin'.
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