Concerning concealed carry techniques and practices, I have read many opinions ranging from "the sheep are not looking for it and never notice" to "maybe no one has let on they see your not-so-concealed weapon, but lots probably have noticed".
Here's an example on the "never notice" side I observed today.
Today around 10:00, my wife did a bit of volunteer work at a replica sod house in the company of a man and woman who were dressed and "in character" as a couple of pioneer-types living in circa 1880 Colorado. I went for a walk on the prairie from 10:00 to 12:00, then arrived at her spot where I saw that the man was wearing a big western-style leather gunbelt and a good-sized period revolver with about 3 inches of barrel sticking out of the holster. It was a left-hand draw shoved around so it hung on his right side with the butt facing forward.
An amusing aside: the guy bent over messing with some gear and I noticed that the protruding muzzle swept me, my wife, his partner, and probably everyone else within 50 meters---but it was properly holstered. Also probably not loaded, but of course we must assume it was.
The point: as my wife and I were walking to the car, I commented on the butt-forward position of the revolver. She hadn't even noticed that the guy was openly carrying a revolver, even after being close to him for 2 hours!