I guess Preacher made my half-joking comment a consideration.
I would understand if they found ammo or spent shell casings, but a spent shell filled with candle/kindling igniter would seem to be self explanatory.

I wonder what would happen IF they found a spent shell/minus primer filled with pot, like Akula described.

I guess you could claim it was a bong or roach clip and see if you faired better being a pothead or a potential terrorist ;D