The rule was created out of thin air by the Wisconsin DNR in 1999.
It starts at your local city. They make up rules as they go. I am fighting it right now.
Exactly right. All regulations are written by one person.
It appears the same person used almost the same wording with regard to bows, crossbows, spears, or similar devices in NR 20.09:
(1) Possess or control any bow, crossbow, spear, or similar device while on any water or on the banks or shores of any water that might be used for the purpose of fishing except as specifically authorized in ss. NR 20.10, 20.15 (1m) or 20.20, or ch. NR 21, 22, or 23.
NR 20.09 allows a few very specific uses of bows, crossbows, and spears to take fish. As all of these are "arms" as defined by the Second Amendment, it appears NR 20.09 is also unconsitutional.