You don't think all those STS-33's and P2P's just get filed away in a drawer in Trenton, right?
Federal law prohibits the ATF from maintaining a registry, and requires the FBI to delete NICS info. after 72 hours. NJ has no such pesky law. Not that it would really matter, as PA state law requires the deletion of transfer records within 72 hours, as well. Ask the PSP how it is they have a Record of Sales database that documents all known firearms transfers that occur within the state of PA - and why they sometimes confiscate legally-possessed firearms from citizens who's firearm info. isn't in their non-registration registry, until such time as the owner can PROVE they acquired it legally.
Lest anyone get confused, and think that NJ is the only bastion of tyranny.