Where do you draw the line?

From my own experience with obsessed gamers whether it be online, PS3, xbox, etc. they can tend to get a little upset when things do not go there way. I would get so frustrated with my fiance because he would get mad during certain games that were not going his way. So when he showed me this video I was taken back to the level of chaos in this video.

The part that gets me is why does his brother do this to him. I remember being a child and wanting to torment my sisters, but this is a little drastic. At what point do you draw the line?