Welcome to the BA board!
If your UK friends are the same age as you, I suspect they appreciate Little Britain as much as you do. It began life on one of the alternative BBC channels and ended up, though in a slightly censored form, on BBC 1. So it has been immensely popular and many of its characters and expressions have passed into the language. Not everyone shares its very black humour (my elderly parents, for example, don't like the throwing up, the bittie or the sketches with the young chav lusting after his mate's grandmother)

Note that by no means all the characters are 'chavs', though I think, in Little Britain, they usually wear trakkies to indicate when they are!

Glad you enjoy it.

Edited to add:
Now I've seen Jenbel's reply, I see that you might have meant, is it 'chav' to watch the show and not is the show an example of 'chav' lifetsyle.
I'd totally agree with her - I doubt it's on the chav viewing menu.