Ok, we are talking about two different scenarios then. People sitting in your seats and acting like _______s when you want them to move is one thing. Your statement made it sound like "I had to pay a lot for these tickets and so should you". Ushers are there to resolve issues like the ones you're stating. IMO, they shouldn't be chasing every single person down to make sure they are sitting in the exact seat they paid for when the dome is 15% full.