Thanks for that. it is definitely worth repeating.
It should also be noted that most --if not all-- tables at gun shows are usually sponsored by FFL holders so there are very limited opportunities to buy a gun at a gunshow without a background check.
And the ATF is at most every show. If it is apparent that someone is making a business of selling “personal” weapons, then they will be in a world of hurt.
A gun show allows nothing more than can be done between any two private individuals.