Let's see if I can make this short, sweet and to-the-point:
Bandwagon fans - Live to boo and bash rather than cheer and support, give up on the team when there are still TWELVE GAMES LEFT in the season, turn on players as soon as they have a few bad games and call for them to be benched (the "what have you done for me lately" mentality).
True fans - Don't.
It's really that simple
BTW - this is not meant to call anyone out. None of you fits my description of a bandwagon fan and I would never question your fan status. And I really do take great offense to being called a "blind homer" just because I choose to keep the faith rather than throw in the Terrible Towel. But hey - if standing by my team through thick and thin makes me a "blind homer," then so be it. At least when I wake up in the morning, I'll feel good knowing I was there to the bitter end.