A London based design firm designed seats that could be adjusted to fit oversized passengers, but this just means making everyone pay for the gap in between. This doesn’t seem to solve the problem because now thin people will pay the price and overweight people will still splill into their allotted space, so agreed, someone needs to solve this problem still.

Transforming Airline Seats Adjust Width for Each Passenger

Link: https://www.wired.com/2013/11/ad

A London design firm has come up with the Transformer of airline seats that would allow an airline to adjust the width of the individual chairs between flights based on passenger needs.