Knife paranoia isn't limited to Europe. I had to take a drug test for a job and emptied my pockets into a tray. The medical assistant got wide eyed- 'You carry a knife! uh, wh-wh -what do you do with it?' I replied 'I cut things.' I walked into the bathroom as she attacked a FED EX parcel shipping tape with her car keys.

later I testified in our local small claims court. I ( in spite of myself) haven't been in a courtroom in 20 years and forgot how things have changed. My knife set off the alarm and back into another tray it went.
After court I went to retrieve it and was informed it was in the sherrif sub station office BACK INSIDE. So I walked back into court, the officer handed it to me and lectured me to leave it in my car next time. I'm standing there, with the knife and asked how I was supposed to leave? He sarcastically sugested walking. So I did, past all the Judge Judy types with my knife, past the checkpoint to my car.
We live in a sometimes illogical society that doesn't logically reflect the real world. you just have to -be equipped to survive it.