The name of the game is fear.
That's right, by breaking open a CD into jagged shards, you too, can stab your fellow crew member in the neck.
Plastic knives? Jabbed in the eyeball.
What about a ceramic blade hidden inside a shoe?
Bic pen?
Long crusty nails?
I can strangle you with my tube socks.
Anthrax make-up kit.
Martial arts master, able to mortally wound a person with one hit. Should be band his entire body?
8 cans of cold beans, enough gas to wipe out a small passenger plane.

See what I mean, those silly rules are meant to keep honest people honest. If you really wanted to, I'm sure you could find a way to sneak a deadly weapon on the plane. Why don't they just put a metal door to the cockpit on the plane.