Actually....why NOT start basis fares on weight? It would maybe encourage people TO actually try to live and eat healthier. A heavier person does require more fuel, etc....so, it isn't a discriminating factor based on a person's looks, but upon a cold hard cash factor in that it is more $$ to fly that person than someone that weighs less. I know the money is a drop in the bucket on one flight, but it adds up significantly over the airlines' fleets.
I'd be all for that.
Sure. Sounds great. Now, why don't we just take it a little bit further. Males statistically weigh more than females. Taller, stronger, more muscle build by nature. Why don't we charge males more than females to fly?