^ yes one of the true imponderables of the universe We need an intelligence committee meeting on this. Not the 4 bullets, but the question about the bullets.
Now back to the original question: Never underestimate the sheer slack jawed stupidity of a high percentage of the population.
Reminds me of the late Sam Kinison whose angry girl friend packed a loaded handgun (aka spoon) in his carryon to get even with him. Evidently it worked very well back in the early days of TSA.