I'm not saying it "would", just that it "could". While 99.9% of all gun carriers may be responsible, sensible people, there's always that one guy who may panic.
Have you ever seen all the tire marks on the E-way's dividing median? You wouldn't think that there were so many people dumb enough to run into a 7 foot stationary object that has been there for the last ten miles, but there you are.
I'm not saying people shouldn't be allowed to open carry in a gunshow, I'm simply saying I can see what the gun show organizers are thinking
. Someone pulls out their gun to show another, it gets discharged, the guy who just got shot in the arm takes it as an intentional gesture, and things go south. The entire store turning to a western shoot-out was an obvious exaggeration, but even so.