Because carrying a lethal weapon like that gives you a responsibility.
Rights always exist with a co-existing responsibility. The clothing analogy simply doesn't work because her right to wear what she wants doesn't effect others the way that carrying a weapon does. In your first analogy it's the responsibility of the man not to be a dick head, in the second one it's her fault for not taking proper care of her weapon, and if we want to take issue with the law itself, the fact that the weapon was in the open.
Rights always exist with a co-existing responsibility. The clothing analogy simply doesn't work because her right to wear what she wants doesn't effect others the way that carrying a weapon does. In your first analogy it's the responsibility of the man not to be a dick head, in the second one it's her fault for not taking proper care of her weapon, and if we want to take issue with the law itself, the fact that the weapon was in the open.