If you’re an American, it’s almost guaranteed that you know someone who cares a lot about football. (Maybe that someone is you!) Imagine watching that person watch their favorite team play their biggest rival. The quarterback makes a pass, both a receiver and a defender jump up toward the ball, their bodies collide, and the ball falls to the ground. Is it pass interference? You know for sure what your friend’s answer is going to be even before they inevitably yell it at the top of their lungs—if the defender’s on their rival’s team, then obviously it’s pass interference, and if the defender’s on their team, then obviously it’s perfectly fine.
Now, clearly this is irrational. Just because a defender is on your favorite team doesn’t mean it’s impossible for him to commit pass interference, and just because a defender is on your rival team doesn’t mean it’s impossible for him not to commit pass interference. But the irrationality isn’t a big deal. We do lots of really dogmatic and irrational things when it comes to sports, and it’s fun and exciting and not a big problem, because in the grand scheme of things, it doesn’t actually matter who wins a football game (sorry).