Why?
The check-in desk guy saw the Canon AT-1 around my neck while he was tagging my gun and told me I wasn't allowed to take pictures. I was sort of surprised, and I told him I wouldn't take any. I was a little disappointed because I had figured a gun show to be decent ground to get some interesting photos, given the interesting equipment, varied people, wheel-and-deal atmosphere, aromatic soap-and-candle sellers, and humorous prices on absolute junk. I hadn't specifically gone there to take pictures; I just take my camera nearly everywhere.
While I was walking around other people at booths saw my camera, even though it was mostly under my coat. One of them said I wasn't allowed to have cameras in here; he seemed upset that I had a camera, even though I wasn't using it. I told him the desk guy said I just couldn't take pictures. He went aggressively silent. Another booth-owner told me I might want to hide my camera, because earlier they made someone go back out (into 10F/-12C weather) to put his camera in his car. Others noticed the camera with obvious suspicion, to the point of effecting the mood of how sellers treated me.
This whole experience was interesting to me on several levels. If I go to a camera convention or something in TX, I fully expect to see a 30.06 sign, just to complete the circle.