Just because someone has an ADF ID does not mean they have an "NV 1 or 2" clearance. Nor does it entitle them to wander wherever they like. If they're in mufti, merely producing an ADF ID and asserting a level of clearance (which they wouldn't do, anyway, if they in fact had that level of clearance) isn't some kind of carte blanche.
I can just imagine some poor bigger from the Upper Gascoyne who uses his C150 to muster a few droughty cattle and makes occasional trips to Carnarvon for supplies having to front an IB somewhere sometime to prove he is the person everybody knows he is for a 1000 miles around.
Sounds like the profile of a typical terrorist, Kaz!
Everyone knows ASICs are about providing a facade of security. In politics, perception is fact.