I don't have sky so I can't watch it, I do think people use the term wrongly however the term working class is also used in the wrong way.
The term I like to use is scallies, and to be a scally not only do you have to meet some of the stereotypes but you have to swear a lot, be insulting, drink white lightening on the park bench, kick up a fuss when the bus driver dosn't believe you're under 16, cause a fight in their favourite pub - usualy Yates.
To be a chav in pictures
Step 1 - Look like this:
Step 2 - Have several buy one get one free alchohol pops here
Step 3 - Drive home in somthing like this
Of course not everybody who looks that is a scally, not everybody who drinks in Yates is a scally, and not everybody who drives Nova SRis are scallies, there lies the problem, As Morrissey would put it:
"You buy the daily news people and find everything in it but the news, but still you look down on the teenage dad on his estate"