David,
Actually it was written by a yankee..or carpetbaggers.. right after the civil war to try to control the unruly populace. It has never been taken off the books. There is a movement afoot to make open carry lawful, but I imagine it will be a long time coming
You just wear it concealed, and there is no law against showing it off to your friends while at the BBQ (as long as you are on private property) Actually, if you are on your own private property, you can carry it openly.
Another silly thing, you can't carry a handgun, bowie knife, or sword openly in public, but it is not against the law to walk down the street in the middle of a city or town with a shotgun or rifle.