Man, some people don't know what actual bullying is if they think this is it.
It's not the same as physical, real life bullying, obviously, but if the reason for it is as stupid as the excuses given so far then it's clearly something like bullying. Just like the way the assholes treat Bushy is something like bullying. Of course bullies aren't going to acknowledge it as such. I suppose you could be generous and say it's just assholes being assholes.
It's just another chapter of the Lord of the Flies. But up to a point, and depending on the person, it's a useful exercise with which to develop the skills needed to cope with this sort of cruel banter in an intelligent - and effective - way. One will have to interact with jerks from time to time over the course of their lives (as I am sure that you well know), so the sooner one figures out a good approach for them as to how to cope, the better.