Yeah that's what I thought at first, but then again, Coyotte is right when he says that you just have to pass each round and won't be losing elo anyways.
That is fair towards people who still want to continue playing even when somebody has dropped. I agree with you that, for me, a game is over as soon as a player drop, but many users here like to keep on playing. And after all it is just a minor nuisance having to click the "pass" button 3 or 4 times...