Fair few lads over here in WA but most jsut refer to 'em as graffers; which is a shame, because whilst there are a few damn fine can artists in the crowd most of them are just wannabe fucks who bring shame to graffiti art by scratching train windows and artlining everything they can touch.
As for dress codes; a few of the doof crews over here for a while tried out a 'No phats' policy, just because the only times problems tended to arise was phattied-up ravers off chops on gear and pills, but it didn't last long because everyone agreed it was kind of against the spirit of doofing... I can udnerstand why the promoters are doing it - As mentioned, phatties are kind of a big sign that says 'search me' to the police, but also, they are excellent for concealing drugs, weapons etc... But that's the punter's issue, not the venue's. Cops will hassle you if you dress in a manner commonly associated with a drug using crowd, that's your problem, and if you're willing to do so anyway then more power to you. Venues shouldn't try to enforce that.