Where I live, I wouldn't be surprised if I walked past a handful of people with a gun in their waistband at the grocery store. Or a couple at the gas station. You don't even need a permit to do so here. And I have yet to end up in the middle of a shootout. Probably because the risk is too high for criminals as the barrier to entry for defending yourself is essentially zero, except for the price of a gun and ammo.
The nice thing about that is it has a "herd immunity" effect. If many people carry around you, but the criminals don't know which person that is, they're likely to refrain from picking on anybody directly. You don't even have to carry yourself to benefit from it.
The only crime that happens often in this city, despite that, is parked & vacant cars getting smashed into and robbed. Because it only happens when nobody's looking.