Indeed I have and still US security is the absolute rudest security I have encountered.
I'am never rude to the security. We let them do whatever they have to do. However I have found many of them to be extremely rude.
The limit is for International Visitors, you have to fill out extra paperwork if you are over the threshold. We always have some money in our own currency to use when we are at the airport. As we had used less than we normally do, I had $50 remaining. As this put us over the threshold, we had to fill out another form. I had no problem with this (which you can't do until you arrive in the US) What I had a problem with was the female security guard who demanded we get out of the line, marched us over into a corridor, was rude and attempting to be intimidating. Made us literally wait over an hour to fill out one form when there was no need. We ended up with an apology when I demanded to see her supervisor. She was entirely in the wrong for her behaviour and making us wait so long (there wasn't anyone else waiting, it was just more of her "intimidation" tactics clearly) Over $50. Not once we were rude, however once it got to the hour, I asked for a supervisor as we were going to miss our next flight (we made it with 10 minutes to spare - and our gate was only upstairs!) We hadn't been rude, hadn't lied about the "extra" money, but apparently because we hadn't filled out the form (which we actually couldn't have done before we saw her anyway) we were somehow in the wrong?
If this was a long incident, it wouldn't overly worry me. However this happens constantly and I have had it happen to me more times than I care to think about.