For one thing, it would be a logistical pain in the @ss in terms of: (1) the reservation process (is the fare based on the passenger's weight at reservation time, or at boarding time), (2) airport operations (as if any airline is going to implement a weigh-in process that actually works efficiently), and (3) the legal process that would bankrupt any airline that tried to do such a thing (Do pregnant women have to pay more? Do people with wheelchairs have to pay more?).
I guess it makes sense, but I can’t say I’d fly on the airline that tried out this policy. I’m a reasonable size and am comfortable sitting in the airplane seats, so I’d probably even get charged less this way, but still I’m not as young or thin as I once was and I don’t want to be publicly weighed by airline workers, thank you! Those people are rude enough as it is without discussing my weight with me. :P
It will not survive attacks based on race and sex discrimination, and especially not the Americans with Disabilities Act.
Does this mean they’ll be going back to skinny young stewardesses? and not heavy bitter old shrews?