The mindset is different here than in Canada - of both the owners, and the "establishment". Contrary to what you infer, most people don't open-carry to show off. Arizona is an open carry state. if I'm going to have it with me in public, it has to be open-carried; it can't be concealed unless I have a permit. The permit requires an 8-hour CCW class (which I am taking next month). As an example, if your handgun is in your vehicle - you may consider having it on my seat in plain sight "showing off". Rather, I can't put it in the glove compartment or under the seat, unless I have a permit. A day at the range, I can stop at the grocery store if I want. None of this "fully-cased and locked, directly to-and-from the pistol club ONLY" stuff. I guess - the establishment figures that if people constitutionally have the right to carry their gun; then they want them in plain sight.
In open carry states, it doesn't cause as much a stir as you might imagine. And most people that I know who carry, open or concealed, I wouldn't classify as "gun nuts".