theft, pirates, anyone?
When I was in the BVI many years ago, during check in, doing the custom and emigration thing, they asked if there was a weapon on board. I said yes, they signed for it and the ammo and locked it up with all the other honest boater’s guns at the main police station in Roadtown.
If I had said no, I would have been able to keep it on board, which is the original intention, of course, but illegal. If they thought I was lying to them, and they then searched the boat and found the gun, then what? Take the boat and (God forbid) possibly the boat???
Damned if you give the gun to them and should really need it later, and damned if they search the boat and find the hidden gun.
Maybe the right answer is to give them a gun without a firing pin, so nobody will get hurt by it, and keep the other (working) gun and ammo very well hidden but easily accessible.