You've made an incorrect assumption. As a callow youth I was foolish enough to think it was "funny" to go after some mellons with a buddy that was always leading me on childish adventures (we also had a bottle of vodka that he'd stolen from his parents and had plans to test the watermelon/vodka myth). We both got peppered with rock salt for it. We certainly weren't at point blank range, but I remember it burning like I'd gotten salt in a wound, but it didn't just go away. We had to pick the stuff out of each other's backs. The fact that it didn't kill either my buddy, me, or your friend makes the point, not denies it.
When your life is threatened using rock salt is legally and tactically idiotic.
