OK, I shoot a muzzle loader.
Therefore my empty cartridge case is ... a loaded cartridge minus the powder and bullet, which = thin air!
So an empty cup holder in my car is an empty cartridge case for my muzzle loader.
I am in BIG trouble.
The precedent for this is when we let jurisdictions all over say that an empty beer can in a vehicle is the same as a full beer can. Once you let the legislatures rewrite reality using the law, there is no telling where it will end.