Everyone knows that certain gun shows are massive laundering operations for stolen weapons. The FBI has straight up stated that a large number of guns which are used in crimes in the Northeast can be traced back to gun shows in Virginia specifically. If you “look the part” it is trivial to get basically any common enough gun at a gun show just by doing a deal in a parking lot, since it’s completely legal for an FFL to gift any gun to an associate, and completely legal for that associate to sell it to you in the parking lot. Cops literally watch this happen because it is legal.