I disagree with your definitions.
Fan: you support the team whether they win or lose, but you are in tune with the players and can be realistic with your expectations. You may not think you will win every game, but you WANT to win every game. Criticism is also acceptable.
Bandwagon fan: you chose the flavor of the month/year. Change teams often or you have several "favorite" teams.
Using the above definitions, I would be a fan.
:yeah
Calling someone not a fan because they believe the team will lose is ludicrous. Even when TO was coach, we played some games where we were horribly outmatched and most everyone realistically thought we'd lose. How many people can actually say they thought we were going to win every game when Clownahan was coach?
Bandwagon fans are those who follow the winners. When I see people from Nebraska wearing Texas, Florida, OU, etc. hats, shirts, etc.; is when I see bandwagon fans. Anyone remember all the Husker gear out there back in the 90's? Some/a lot of these fans are/were bandwagon fans as well. A fan supports their team in the best of times and the worst of times. A bandwagon fan always supports the winners.