We live in Dunsborough (when not free camping around Australia). The problem is these Dunsborough campers won't walk the 50 metres to the toilets. Walking around these car parks is a challenge, at least dog owner pick up the poop. These "wizbang" campers will also stop on your front lawn leaving behind poop and rubbish. The whole place stinks like the back streets of Asia. Most people I talk to don't have problems with the camping as such if they would only use the toilets and rubbish bins provided.
Don't worry about on the spot fines, just use a fire truck and hose the whole place out. The insides of these wizbangs are as bad as they leave the outside so wash that as well.
Some parks in Perth they have automatic sprinklers come on early hours of every morning. That solved the camping problem. These campers don't like water (or washing).
Some interesting comments on the link Paul, I suppose the town does get some benefit from money spent in town at the shops etc but not sure how I would feel if I lived there. I don't think I would like to live there from the reports of schoolies antics during school holidays.