It's no big secret that the heavier a plane is, the more fuel it burns.

Planes gain weight for a variety of reasons: passengers, cargo, liquid holds, etc.

Airlines have become quite happy to charge extra for "overweight" baggage.

But I say why stop there?

Why not implement an airline business model that focuses on charging passengers based on their weight (body and luggage), so they're truly chipping in for their portion of gas?

For example, I'm about 6'1" and weigh 175lbs. Clearly it takes more fuel to fly me from JFK to LAX than a 5'3" 105lbs blonde [OT references edited by mod.]

OTOH, [the petite traveler] might have two 50lb bags in the cargo hold whereas I only have my rollaboard and laptop bag.