MrWCF: Oh yes, I've noticed it as well. It annoys me too. I've even been yelled at for resigning with the argument my opponent didn't get the satisfaction of "moving out the last stones".

But there are other sites where it's worse. There's one site I play where resigning is actually punished (you get extra negative 'tie breaker points' making it harder to win a tournament if another player scored the same amount of match points).

As for your point 3), I've heard that often. I don't buy it. Little skill is needed to play out a position where the situation of the opponent is hopeless. No tactical or strategical action will happen that will be useful to the losing player. If the losing player wants to learn something, he'd be better off starting a new game instead of continuing a game that's lobsided.