Concur.
I think this really is a significant issue that needs to be addressed.
Aircraft manufacturers are squeezing in seats, but people are getting bigger.
It is time to be realistic, and load the aircraft accordingly. Hell, if nothing else, you can get more freight on the ac...that is where you can make money. The ac is overweight, with min fuel load...just like the 'blind' scanners, they could have a pressure plate to weigh everyone at the gate.
In reality, 17 and 18 inch seats dont work, make the seats 24 inch and charge more for a flight.
(charging for 2 seats, damn, have you ever tried to sit on 2 seats?
)
EDIT: I did work with one Chinese airline that did weigh everyone. Landing conditions were extreme, so they did an exact balance for the weight, as freight was very, very important. I thought it was a very, very good way to do business.