I don't see this as a dumb rule at all. if the gun is not in use, it should be unloaded. A gun being kept in a nightstand or in a hip holster for defensive purposes is in use. Note the rule does not say "ready to shoot", but "ready to use".3. ALWAYS keep the gun unloaded until ready to use.
Rule 2 is the one that mentions ready to shoot.2. ALWAYS keep your finger off the trigger until ready to shoot.