Quoting some guy from the internet
Just ask the rangers politely to "define camping". Not one has ever been able to tell me in ten years of motorhoming, especially when you are only sleeping in your vehicle.
One ranger in Broome got so frustrated trying to define what camping is to me. It went something like this
"What is camping?"
"Well, camping is when you light a fire"
"Not doing that!"
"Ummm camping is when you put up a tent"
"Not doing that either!"
"ah! camping is when you sleep in your car!"
"during which hours?" I asked
"well, from the time the sun goes down til it comes up again" he said
"so if I sleep all day and stay awake all night then I am not camping, right?"
At this stage he jumped in his 4x4 and roared off in despair. So know what I mean.
The other trick is to speak in a foreign language and he will back off quick. No point giving you a fine because he knows he will never get it paid. It takes practice, but it works a treat, provided you can stop the wife and kids from laughing.