I remember sitting in the KG5 night club in Berlin circa 1980, watching the floor show with my crew, when a group of 'elderly gentlemen' entered.
One asked me if i was in the services, and I told him to mind his own business - it was Berlin during the cold war after all.
He then asked me if i was ashamed to admit it, and I said no, but it may pay to be discreet given where we were.
He then said that he was military, as were all his companions and showed me his ID. I said that it had no service number on it.
He then said that 'my dear boy, when one hits 2 stars and above, they don't bother with the number!'
I made my excuses and left.