SeagullSongs
And it's all gone quiet..
If true, that's just plane stupid (see what I did there?).
Just think of the extra fuel needed because of the extra weight.
easyJet use Airbus A320s, they hold up to 220 people. 20% of that is only 44 people, or about 4 tonnes for the people and their luggage. The A320 has a maximum take-off weight of 77 tonnes so it doesn't make an awful lot of difference. Plus they charge you to take luggage on board and more people equals more food and drink bought on the flight. Aviation fuel is relatively cheap as well, it's only about 75p per litre because there's no tax on it.