An interesting thread, but the replies reveal much more about the posters!
I had a similar situation in LAX with a moneybelt - I don't trust myself not to lose a wallet from handbaggage or pocket.
The security operative stopped me after xray arch and asked what I was wearing under my shirt. I revealed the money belt and I insisted that I watch it go into the xray machine and out of the other end. No problem at all. No interest in content as long as it was safe.
I wonder what the reaction of a US citizen would be to being asked how much money he was carrying in a wallet by someone whose job it was to check for arms, dangerous goods etc/ They would not tolerate it and they would be right. Might even resort to law!
The OP was dead right to refuse on the grounds that the demand was entirely outwith the brief of the person asking, as proven subsequently.
The more people comply with such excesses of authority the broader and more intrusive they will become.
Well done robtheblade!