That is stupid in the extreme! If he were to have gotten shot, I wouldn't have much sympathy.
I suppose his demeanor would have played a role in how I would respond.
But lets face it folks... Working the counter at an auto parts store IS NOT the same as working the counter at a gun shop or pawn shop! You don't expect someone to come up and plop a handgun down on the counter whether it's in a holster or not.
I'd venture to say that if an experienced cop who works a high crime area known for armed robberies were standing behind the guy when he did that, he'd have drawn down on him in a heartbeat!
That looks dangerously close to an armed robbery to me.
I say that, because I've seen a couple of closed circuit video's of armed robberies where the robber did in fact lay his gun down on the counter as he announced his hold up. Granted, in none of them was the gun in a holster... but the thing is, who knows what's going on in the mind of the guy doing it? I can't read minds...