[Strangler Lewis]

I don't think this about passenger comfort at all. The airlines have been jettisoning all sorts of things trying to shed weight and save on jet fuel. The reality is that one obese person forced to buy two seats will generally mean less overall weight in those seats than two average overweight Americans.

If it was about passenger comfort, there would be all sorts of different fares, classes and cabins:

"Won't shut the f*ck up" class.
"Won't turn off cell phone until threatened with arrest" class.
"Insists on looking important by calling someone to say they've landed as soon as the wheels touch the ground" class.
"Last to board with a carryon that requires reshuffling of all overhead bins" class.
"Stows bunched up sweater in overhead bin on crowded flight" class.
"Blares music through headphones that I can hear three rows up" class.
"Falls asleep against window during drink orders" class. (Tap. Tap. "Excuse me, did you . . .?)

And so on. These people should all be charged extra. Or just given a good horsewhipping on the spot. Which I would pay extra to administer.