I'm reminded of a time when as a moderately junior boffin at Boscombe Down I was sat opposite a middle aged gent who appeared to be a Captain RN (blue jersey, four gold bars), and thus was being particularly polite and calling him sir.
Half way through lunch in the mess it finally dawned upon me that this character was the PA31 air-ferry pilot from BAe, just eating lunch while his boffins talked to our boffins, so that he could fly them home.
What's the penalty for impersonating a Captain RN ?
In the meantime, I bought a set of gold bars when I got my CPL, in case they ever came in useful. So far, they haven't, and are still somewhere in the bottom of my flight bag. I never got as far as buying the flammable polycotton white shirt, but might if I have occasion to fly in some parts of the world.
G