I honetly feel that full looting will always be a part of the game, and, you're going to have to learn to live with that. That being said, I think that most reasons for full looting someone are simply malicious. It's basically one player trying to be the biggest, demoralizing asshole they can be. They are sending a message to the other player that they WANT to make their playing experience as miserable as possible. It is not only incredibly poor sportsmanship but I feel it reflects a low moral base of that player. Winning simply wasn't enough. They had enough hateful feelings to do everything they could to tear that person down and probably took joy in it. I don't know how many out there in the player base have been involved in athletics. I was in HS and college. There is a reason why sportsmanship is mandatory at all levels, from amatuer to professional, in every sport. It is because it is healthy for that sport overall.

This is a competitive game, afterall, and I think good sportsmanship should be just as mandatory for the game as roleplaying is. I think in the longrun it would provide the playerbase as a whole with a more rewarding experience which will obviously lead to player retention and interest in the game.

If you want to be an asshole. Go be one to your friends and family. See how far that gets you, assuming you have some left.