I invited my crew to watch (discretely) as I successfully transited the outbound checkpoint with a credit card in the i/d holder on my uniform.
Back in the eighties, I was seconded to a Base Workshop, the manning of which was 90% civilian, 10% military (I was one of the 10%). The security was provided by MoD Policemen and we were never surprised by the "identification" which allowed us to access the secure compound. Flashing a pack of Embassy Number 1 cigarettes always worked, a Mickey Mouse Club card worked as well but the best was a home made ID card naming the holder as "Elizabeth Windsor" with a picture, taken from a glossy magazine, of Her Majesty the Queen.... The fact that the person using the card was 6 foot 4 inches tall, bearded and spoke with a Glaswegian accent was neither here nor there....
If it hadn't been so serious, it would have been a laugh.....