Or to beat the hell out of that idiot.
You are advocating aggravated assault because ...??? The idiot(s) in this case appear to be the portly gentleman who trespassed on his neighbor's seat, and the airline which allowed him to do it. If you're going to occupy more than one seat, you should pay for more than one seat. If you don't want to pay for more than one seat, don't fly. Or visit your physician; he might be able to assist you in shedding the excess avoirdupois.
AB