Rocker Rick (no pun) Derringer was arrested a while back for a handgun in his carry on bag. "He claimed" I've been touring/flying VERY often (30ish years) & have ALWAYS had my handgun in my carry on bag.
Like with fishing, you can't catch them all, but come on.
Like the "secret" handgun pocket in fanny packs, the "secret" gets out, after a while.