Worst gold bar abuse I've ever seen was the BAe PA31 ferry pilot from Warton who used to go into the mess at Boscombe Down in a blue sweater with four gold bars on his shoulder. Yes, I too mistook him for a Captain RN pilot until somebody quietly whispered in my ear to treat him like the bottom-of-the-ladder contract pilot he actually was.
I got that beat Genghis. Back in my knocker days at Cornwall Finest Airbase, I spotted a knocker "mate" (Sergeant Aircrew for those that don't know the lingo) wandering up the main drag wearing bars and and scrambled egg hat - He had a PPL - and he actually took a salute from an airman wandering past.
Apart from being an utter tw@t thing to do, I'm pretty certain he could have been charged for impersonating an officer.
That was decades ago...a few years back his actual name appeared on here; somebody was checking him out for boasting about a fast jet background which they suspected he did not have (they were right).
Once a walt, always a walt, I guess.