with my experience working with comair, chautauqua, freedom, skywest, shuttle and asa, i must say comair(and i am not being bias) definitely does not tolerate that. i've had a flight return to the gate when they were in position holding for takeoff just to put a passenger off. chautauqua on the other hand in my experience would more deal with the problem once it is not tremendously out of hand. the others just fall into place somewhere in the middle.