Since total confiscation and even regulating all private transfers isn't too palatable to the general population, this spurs the gun banners to make up the gun show loop hole.
The firearms laws don't regulate "sales". they regulate "transfers". A very important distinction. You can buy without transferring and you can effect a transfer without buying. Gifts or even LOANS are considered transfers. Think, letting someone shoot your gun at the range as becoming illegal without an FFL to process paperwork and perform background checks.
Having made up the gun show loop hole as a step toward total control, definitions of what constitutes a "gun show" become ominous and starts to infringe on the 1st Amendment. The right to peaceably assemble. I've read some of the proposed legislation. One, IIRC, defined a gun show as ANY meeting between 2 or more people (like you could have a meeting with less than 2!) whether in person or through some medium, with or without firearms present, pre-planned or not, that initiates what ultimately ends with a transfer of a firearms. Then, they put the onus and penalties on the "gun show organizer" who has to register the meeting, file paperwork and insure compliance by all parties. Pretty tough to do at an impromptu encounter.
So if a co-worker casually mentions he always wanted a .357magnum and you say, I have one for sale, that's a gun show. Not only would the transfer have to go through an FFL, but the gun show "organizer" (your boss who wasn't even involved) would be subject to penalties for holding an "illegal" gun show. You think that's crazy? Crazier than declaring washers as silencers?
Scary stuff. That could shut down all gun related forums whether they have "classified" sections or not. Actually some of these proposal would do more harm to firearm ownership than an outright prohibition on private transfers.