[Kuiper]

Is BMI a relevant factor in this discussion? The author's point is that higher weight = higher cost of transportation due to fuel costs. If you're a tall person, it may not be your "fault" that you are heavier than average, but that doesn't change the fact that someone who weighs 200 lbs adds more to the fuel costs of a plane than someone who weighs 150 lbs.

The goal isn't to judge people based on whether they are "overweight" or such, but rather to institute a system that charges customers proportionally to the cost of transporting them.