Chav is just one in a long line of derogatory names for people who I guess would be classed as white trash. It just seems to have really been taken to heart over here in the last 7-8 years.
Yob, Kevin (apparently all such people used to be called Kevin or Sharon), manger (pronounced mang - ER), Chav etc.
Lots of sportswear for the unsporting, lots of Burberry.
I've seen that bit in the etymology elsewhere:
Many folk etymologies have sprung up around the word. These include the backronym "Council Housed And Violent", and the suggestion that pupils at Cheltenham Ladies' College and Cheltenham College used the word to describe the young men of the town ("Cheltenham Average").[not in citation given]
I went to Cheltenham College and I'd never heard the word until it started getting used in the media.
Hate the expression because it's just an 'I'm better than them' word.
Still, there is some utter scum living in this country.