Re: If weight is such an issue...
Well then just apply a total weight allowance for passenger AND luggage. When you check in you stand on the plate with your bags. Over the weight allowance you stump up. If you come well under then you can get a discount.
It's going to happen one day.
Airlines will also then get fairly accurate info on how much weight they are carrying per flight. I would have thought that would be useful info to have.