My ex-wife and I were carded in Denver when we were both about 40, and were refused admittance even though we showed our papers.

In this case it was because they were getting a lot of "marginals," many with fake ID, and we arrived in between a couple of "questionable groups." They were carding everyone to avoid arguments about "don't I look old enough." The refusal was because they had posted "photo ID required" due to large numbers of forgeries, and the only identification the ex had was her Kansas drivers license, and those didn't have a photo at the time.

I'm afraid I'd have trouble with working in such a place now, because at my age all the people working in such places look - to me - like they're about 12 y.o..

John