I bullied a bit in primary school. I was bigger than most of them, so I had the opportunity. This is why I did it and they didn't. It's just human nature. It feels good to dominate, so you'll do it given the opportunity. I'm not even sure if I did bully actually...can't remember. I'm told that I did at times. The other kids' mums all hated me and invited the whole class but me to their kids' parties and stuff. I think it might even just have been that we did playfighting in the playground, but I was bigger and stronger than the others so ended up winning and hurting them. Anyway...
Then I entered high school pretty depressed and mute, so was an easy victim and got bullied, the bullies including the weak guys from my primary class, their force strengthened by new friends. These weak guys from primary also bullied lots of the other weaker kids at high school (who had never done anything to them), laughing as they reduced them to tears, doing things which I'm absolutely certain I never came close to in primary school. They never did anything unpleasant in primary school, because they couldn't. I ended up being pulled out of that school by my parents because, even though I wasn't talking about it, it was very clear what was going on and how bad it was.
So I think the bully in the video is probably only about as bad as anyone else really. It's just that he's had the opportunity to be how he wants, while the weaker kid hasn't.
Anyway, now we're all grown up, I think that out of my primary class, I'm probably the person who gives the most to charity and so on, and I was originaly the bully (I think), so...