Well, I can tell you that in California, (if you live in a county where you can get a CCW [mostly anywhere north of Sacramento]) the law doesn't actually require that the firearm never be seen for CCW.
We also don't have any exceptions in the law by which a business can exclude us, although carrying in a bar is verboten.
Ironic, isn't it - a state like CA having reasonable laws sometimes?
"Concealed means concealed" is what they are teaching in the CCW classes, however, as of the last renewal I did. I was tempted to call the teacher on it, but I didn't really want to make the class any longer.
Dex