Of all your points I have a hard time following this one, it's like a part of me is betraying my favorite team or player and you always wish that your team or player can and will upset the opposing team, I experience losing in the past, that is why I prefer not to bet when my favorite team or player is against a very tough opponent and I have a small chance betting on my favorite team or player, I prefer this than betraying my favorite team or player.
Actually it is not too hard to believe that your favorite team can be optimistic to win every game even against a tough team, the last few football schedules we have reviewed that a strong team is not always guaranteed to win the game even have been beaten by a lower team, so in analyzing team based game so we have to control bias behavior in deciding that our team has some sure points to beat the opponent and don't care even if betting for tough opponent.