I'm getting the idea that the complainers don't really know what they're looking at and conclude its trash at high prices.
The idea I get from above is that gun show attendees are disappointed when they spend a lot of money on gas to get to the show, maybe shell out a bunch of money to park, pay a high entry fee, in the process using up a good portion of a precious day off, only to find 800 dollar run of the mill 19's, 800 dollar refinished HD's, flea market stuff, etc. It could be they don't know anything, or it could be they've seen a general deterioration in the quality of gun shows and are commenting on it here.