Antique longarm treansfers.

Ok, so I know Handguns are handguns regardless of the federal definition of a firearm. This is easily found in the law and that is not what I am asking.
 
I am interested in where (if) antique longarms are defined in any way in NJ other than the federal definition:

A. Any firearm (including any firearm with a matchlock, flintlock, percussion cap, or similar type of ignition system) manufactured in or before 1898; and

B. Any replica of any firearm described in subparagraph (A) if such replica:

 

1. is not designed or redesigned for using rimfire or conventional centerfire fixed ammunition, or

2. uses rimfire or conventional centerfire fixed ammunition which is no longer manufactured in the United States and which is not readily available in the ordinary channels of commercial trade.

C. Any muzzle loading rifle, muzzle loading shotgun, or muzzle loading pistol, which is designed to use black powder, or black powder substitute, and which cannot use fixed ammunition. For purposes of this subparagraph, the term antique firearm shall not include any weapon which includes a firearm frame or receiver, any firearm which is converted into a muzzle loading weapon, or any muzzle loading weapon which can be readily converted to fire fixed ammunition by replacing the barrel, bolt, breechblock or any combination thereof.

 I have only found:
 

N.J.A.C. 13:54-1.3 Firearm identification card or permit to purchase required
(a) No person, other than a licensed or registered retail or wholesale dealer, shall receive, purchase or otherwise acquire a rifle, shotgun or antique cannon, other than an antique rifle or shotgun, unless that person possesses and exhibits a valid firearms purchaser identification card.
No person shall sell, give, transfer, assign or otherwise dispose of a rifle, shotgun or antique cannon, other than an antique rifle or shotgun, to a person other than a licensed or registered retail or wholesale dealer unless the buyer or receiver possesses and exhibits a valid firearms purchaser identification card.
No person shall sell or acquire a sawed-off shotgun.

 
This would make it seem that they are excluded from even the FPID. So Why do Gun shops demand that these be transferred?

P.S. I have happily paid to transfer long arms from auction sites to ship to a NJ FFL where I can pick them up. I have just never seen where it is clarified that (or if) antique long arms must undergo this same process.