I find this to be a very... narrow view.
I hate violence irl in any shape or form. It's unecessary. But I do like a good gory videogame. Mind you, I don't play these games because of the gore but because they are good games and their atmosphere just happens to be supported by gore. I wouldn't want to play a game with zombies without over the top blood and gore effects. It's just not the same. There are certainly cases where this goes to far, for example the Mortal Kombat games; these are just as gory as possible just to be as gory as possible.
What really rubs me the wrong way is that you're comparing this to real bloodsport that happened in our history. Just because I like some heads exploding in my videogames and movies does NOT mean that I ever want to see something like this again. I really don't.
That said, yes, the first Episode in the first Season was by far the worst and I did find this scene to be over the top and unecessarily gory. I bet this was more a case of some artists going "hey we never had the chance to do this in any movie yet, let's see how good we can make it look". And yeah, they nailed it pretty well lol.