...and that is similar to charging for multiple seats but often in reverse. In the ‘width threshold’ model they could turn the 3 seats into 300 “seats”. Then the number of seats each person needs would be based on width across the hips with some otherwise very small women paying a lot more than a string bean male.
The point being that giving these companies other “reasonable” methods to abuse some passengers into paying more inevitably turns into a way to make almost everyone pay more.
Fat women could pay more and slender women could get reduced fare for sitting on men’s laps who were willing to pay extra for it.