Yes, I did - in a polite fashion as I was at the time a Fg Off Nav Stude and he was, after all a Flt Lt and much older than I - but he felt it was his right to wear what he liked. Obviously not the case, but I tried.
I had to smile a short time later when he was unceremoniously dispatched from the bar by the CI......
Definitely the exception, rather than the rule though.
Incubus - I am aware that the RAF supports the ATC in the way you point out but the fact is that the cadet organisations would not exist without the parent Service. By 'supporting' I mean primarily recruitment, which has always been a sensitive subject. However, I believe that the situation was formalised a couple of years back and the ATC is now officially a source of recruits for the RAF.
Cheers
SBG