Well, yeah. Court mainly uses it tongue in cheek, like when posting Yinztagram pictures to facebook (or "Go Stillers") or saying "Hey yinzers, anyone want to go out tonight?"

Then there's how people perceive "y'allers." William Shatner made fun of a fan who asked a question of him at Dragon*Con and used "y'all." Leonard Nimoy told him he was being an asshole.