This is simply the way of the Thai male to attack in packs and foot stomping is a particular favorite. Now us foreigners we don't follow those rules as we could see in the video with other foreigners not helping. Guaranteed if a few winn drivers were around they would have joined in on the foot stomping.
I left my pregnant wife and 3 starving kids behind in the USA and began my new life in Thailand. I remember the oldest at the time was 10. Please Daddy, don't go, I'm so hungry.