Unfortunately, this is one persistent "wives tale" that seems to never die. The Virginia references, while good for BBQ vs. tofu, really don't help here, since the assertion is that it is a federal issue, not a state issue.
My first CHP class instructor quite adamantly insisted that this was the case as well. This was way back when I was much less informed than I am now, so I didn't know any better to correct him. I've run into other similar situations with people who think they know more than they do. One particularly annoying security desk clerk at a local hospital insisted that it was against the law to carry a gun in a hospital. I politely suggested that she seek a refund from her "security officer training class", which for some reason was not at all well received...
I was polite, if somewhat sarcastic, and suggested that they try to find the law, if they were so sure it existed, a task which I would bet my bottom dollar was never even attempted.
TFred