Thinking you're better than other people because you're working class, have a regional accent, don't use big words, read tabloid papers, or for other reasons which are opposite to those which would be involved in "snobbery" in the usual sense.
The argument that people who live in "rough" areas are the only ones who "know" about crime and that everyone else should shut up is just an example of inverse snobbery.
The sniffy behaviour employed by a snob. Behaving in a superior fashion to others on account of their perceived (or actual) status in relationship to one's own.
Toff: 'Look at those oiks, they are wearing poor shoes, how ghastly, ugh, wide berth Timothy, wide berth...'
Oik: 'See they uppity nigguhz? Nevah done a day's work nevah. Heh - they all book-lurned n'shit. That's snobbery right there *hokspit*'
When you and a friend are sitting on a bed and a naked 427 pound Korean woman walks into the room with pineapples taped to her thighs and commences a lap dance on both of you at the same time
Me and Nawty got a pineapple shnobler this weekend from Mrs. Lin next door.