The reason for the "gun-show loophole" in the 1968 Gun Control Act was that the Federal Government at that time thought it had to satisfy the Interstate Commerce clause of the Constitution. What the "loop hole" does is except out intra-state sales from the FFL transfer requirement of the Act. That is what allows you (that is the private citizen) to sell or bequest or give a gun to someone who lives in the same State you do without the background check.

All the FFL dealers at any gun-show are still required to complete their background checks just as it they were in their shops. The exception is only for the private citizen, and it is limited to same State citizens as purchasers. I trolled a Husqvarna sxs through the local show here this weekend and the only 'buyer' was a guy from Florida. I told him I couldn't sell to him unless we had one of the FFL dealers at the show document the sale. He declined because those guys were charging $40 to do the background check...Geo

PS: On the other hand he may have declined because he was an undercover BATF&E agent and I didn't fall for his scam!