WyMark, I realize gun owners are not a protected class. I am saying that the moral argument of "private property" has already been shown not to be absolute with regard to businesses open to the public, and therefor I feel no moral anxiety at lawfully - if covertly - thumbing my nose at business owning antis.
In my state, if they notice, and ask me to leave, I leave and there is no crime of any type committed. If I argue, it becomes simple trespass. I would not argue, but they have not noticed in any case.
If they ever do notice, it will be because I needed to display or use a gun, and in such a case I really would not care about the business owner's feelings.
I am not advocating breaking the law, and the law differs by state. I am just talking about the moral side of the house, and if the business owner isn't screening potential bad guys, he is in no moral position to strip me of part of my ability to defend myself.
Edit: part of my ability, because one who trains to fight with his bare hands is never fully disarmed; but, an armed man will kill an unarmed man with monotonous regularity...