Around the holidays they always tighten up security... I think the cutting surface of scissors has to be less than 4 inches. They took me aside last Sept and measured my scissors, they are 3 3/4" blades...So going through the rest of the check points I set them and my embroidery scissors out with my baggie of liquid items and I sailed right through.
I think their theory is that something like that can appear to be intact...but they do not want to take the time to inspect these items to make sure they have not been tampered with.