The reason a lot of "gun free zones" don't work is not b/c law abiding citizens generally ignore them. Recognizing that isn't bogus, so we'll just have to disagree on that general point. Again, it comes down to the criminals. Society can make all the rules it wants, but making rules is all it will be (and we're not merely talking about the example you laid out above). Btw, that doesn't mean you don't have laws or that you don't enforce the ones already on the books. It's just ironic that areas in the US w/very strict gun laws often have higher violent gun crime rates.
As to the loophole in question, unless the "low level accessory" is actually buying guns and then selling them on the black market for profit and using the loophole as a get-out-of-jail free card, then why wouldn't they initially report the stolen firearm in the first place (which is what my point about embarrassment was addressing)?
Now, I want you to remember that no bastard ever won a war by dying for his country. He won it by making the other poor, dumb bastard die for his country.---Patton
There is no room in this country for hyphenated Americanism.---Teddy Roosevelt
I never forget a face, but in your case I'll make an exception.---Groucho
And if you all get killed, I'll piss on your graves.---Shaman Urdnot
How would you like to own a little bit of my foot in your ass.---Red Foreman