Ahh..well, see, that is where it's all wrong you see.
To instill fear into a group of people, because of how they look/dress etc, is wrong....it's much better, to just let them get on with it, so you can openly take the pi$$ out of them.
When I was at school..it was popular for trendy people, (lager louts and tossers, mostly), to go "Sweaty Bashing"...not much fun...problem was, they were only used to doing it, to small groups of people, and when one day they tried their luck on an equal sized group, despite the Sweatys protesting, to "leave it out", they found that a large group of Sweatys, were not to be ferked with.
But Chavs are just tossers.