You know what you can do without physically assaulting people? LOL.
It happens at Philharmagic quite often, because people think a couple of seats won't matter. Well, in my loudest, most professional voice, I cup my hands around my mouth and say,
"PLEASE MOVE ALL THE WAY TO THE END OF THE ROW."
The people that are doing it know they are doing wrong, and usually jump out of their seats so quickly it looks like an electric shock hit them. By the time they realize I'm not a CM they are so embarassed by all the people around me smiling (and sometimes even clapping) that they slink down to the end.
Obnoxious? Only to the "I'm better than anyone so I don't have to listen to Goofy telling me to move down" crowd...everyone else finds it a riot (and I always get a few slaps on the back).
AEfx