The biggest killers were disease and accidents.
Nowadays, Police are people, too (or so I have heard). They open carry for the most part.
You can open carry in a way that is not so obvious, but the mere presence of a firearm is not an invitation to a shoot-out, concealed or otherwise. People tend not to pick fights when there is a reasonable possibility it may get them hurt or killed.
When it is really hot, a small breeze can 'print' your firearm, placing you in violation of concealed carry statutes because your sidearm is no longer technically concealed.
No one is calling for inner city 13-year olds, nor psychopaths nor drunks to be running around with a handgun or other firearms, but when I was a kid, we carried our rifles often in a rural setting, and the neighbors thought nothing of it. (I started deer hunting at the ripe old age of nine, and harvested my first at 11--after having put dozens of ducks on the table.)
It would be nice to be able to transport a hunting or target shooting arm to my vehicle without having to wrap it up and disguise it for fear someone was going to go ballistic and call out SWAT for me going off to the range to sight in a new scope or check out some ammo.
I have hunted and shot guns since I was 12. We had reasonable restrictions; i.e. ammunition in the glove box and guns in the trunk. We never openly carried in the city and we were better off than people today.