I was amazed at how polite people became when I open carried a pistol a few years back. Cars were stopping "early" for me, instead of trying to quickly cut in front of me. In the grocery store, no one was reaching in front of me, and waited until I was done selecting my item before approaching the same section of shelf.

I noticed something else too. I tend to shop by finding empty isles that have items on my list. Each time I would go down a new empty isle, I ended up being surrounded by people. I realized later they were basically following me because they felt safer.