Have you ever been to a gun show when someone was shot by an idiot who left a gun loaded, or loaded a gun then pulled the trigger? How about when someone loads a bullet into a firearm then leaves the table, and someone else test fires it? I have been arond all three. Too many people want to dry fire the guns to test the trigger, even on rimfires. It is a matter of safety, there are too many idiots out there to risk it. Concealed permit holders are OK with me, but the tools who don't follow the basics of firearms safety have no business carrying a loaded gun at gun shows, and unfortunatley, there isn't an idiot detector at the front gate. The promoter sets the rules, guns are brought in to be sold or traded, and too many people don't treat guns with the #1 rule, to treat every gun as if it were loaded.
Every time an accidental discharge happens, it boldens the anti's movement against gun shows. When someone is shot, it can kill the show forever. Promoters are required to carry multimillion dollar insurance policies to cover the show for such things, and if someone is shot, their premiums can and will increase substantially.
I was at the Tulsa show in 1998. A private security guard had his gun checked and banded at the door. The guard goes in, gets to the middle of the show, unbands his gun, inserts a loaded magazine, racks the slide, points it at an unsuspecting bystander's legs, and shoots the gun through his right thigh and into his left thigh, breaking his femur. I heard the shot, and an EMT across the aisle grabbed a first aid kit and ran over to help. All the rules were in place, and it still happened, because many people are idiots, and I don't want them carrying a loaded weapon anywhere near me. The guard went to Jail.
A dealer I know was set up at Hastings a few years back. He claims someone put one round of ammo from a full box into the revolver it fit while he was away from the table. He didn't realize it, and thought he would dry fire the weapon into the table. Bang! He doesn't get to set up at Hastings anymore, period. Who's fault was it? His. He pulled the trigger. What if he killed someone?
Accidents happen, stupidity is rampant, and we need to do everything we can to help prevent those kinds of accidents.