I played softball when I was just a little mandy. I was in right field, and I wasn't particularly good, but I had a blast playing. Some how I came out of it with a few championship trophies and a lot of great memories. At the conclusion of each of our games we would line up as a team and slap hands with the opposition. "Good game. Good Game. Good Game. Good Game. Good Game." I'm sure that a number of you have had similar experiences. We were taught to be good sports when we won and when we lost.
The fascinating part of an esport is that we are not face to face. Rather than bringing out our magnanimous natures, we tend to get cranky in the wake of a loss, and sometimes even after a victory. Karelle of Hydraxis admitted in the general forums the he is a poor loser. He felt he was unjustly beaten by a team that overgeared him and was insulted when the team leader whispered "good game." Rather than repeating the greeting, the original poster /spit on the victor.
The original poster posed the question "Someone owns you, (not just in wow arena, but in anything) and then holds out his hand for you to shake...do you shake it?" I think the answer is yes. By being bratty in this instance, Karelle missed a valuable opportunity to make a friend and maybe even get some constructive criticism on his play style.
Some of the responses would clearly disagree with me. This attitude is exemplified by Malenth of Bloodhoof argued that when someone says "good game" after a victory, they are typically gloating. Fimbulvetr of Proudmore added "That sort of thing needs to be initiated by the loser if it's going to happen at all. Particularly when it wasn't a fair fight."
I'm glad that Blizzard does not make us line up and congratulate each other at the end of a fight. I don't think that would end well. We might do good to remind ourselves of our youth sporting days. What would you do in the original poster or the subjects positions?