No $hit! I never could understand why people want to be band wagon fans. Is it because they have been losers their whole life? And it just feels good to be on the team that is winning right now, so they feel like a winner.
Conversely, it could be they are a 'bandwagon' fan because they are winners in everything they do, won't support losers, like to support winners, and don't give a hoot about sticking with one sports team, or even seeing that it should somehow be a rule for fanhood.
They know a LOT about the game(s), the coaches, the players and the rules, and don't at all feel tied down.
I've got a neighbor like that. Blows my mind. Plays fantasy, football and basketball, in 3 or 4 leagues at a time, can quote oodles of player stats off the top of his head. Lives in front of his TV on Sunday, records ALL NFL games while watching Redzone, and switches back and forth faster than I can keep up. Before they had kids, his wife was the same. He says, even better than he.
Follows the players, not the teams.
It's the ones who
act like they
know, such as the one being described here by the OP, that are a hoot, and a bother. Not the ones who
really do know, like my neighbor. Well, he's a bother in a different way. I'm almost embarrassed to watch a game with him and feel ignert.