The problem is that preserving a firearm for a hundred years is easier than a hoard of ammunition. Both arguments make a lot of sense, and its all about the two sides recognizing entropy is a thing, and despite things making a lot of sense, sometimes stuff go to a way that makes fiction look bland, and its at that time when things that dont make much sense save people. Such as the survival master from the Balkan wars who relied on selling lighter fluid during the conflict