Ran into a similar situation in CUN a few days ago. The Cancun security officer flagged my teen daughter's bag and wanted to look inside. Turns out the 2-and-a-half inch long pair of tweezers was a no-no. He did a great pantomine of getting stabbed in the stomach by the tweezers to show how dangerous they were.

I felt like pointing out several potentially more lethal non-prohibited items in my own carry on, but fortunately resisted the urge.