I know that in certain countries like Japan or South Korea: it’s normal to leave the front door unlocked since the probaility of someone breaking in is low since their crime rate isn’t high. I knew a friend of mine who resides in Korea where they even left the car unlocked with the keys inside, can you do either of those things in America?
I personally have never lived somewhere where I don’t lock the doors, even if I’m home. It just makes me feel safer.
Conversely, my dad, who lives about 15 minutes from me, has never locked the front door of the house in the 45 years I’ve been alive. When he goes away somewhere, he leaves the garage door unlocked so neighbors can borrow tools and the kids in the neighborhood can grab a ball if they need one. Nothing has ever gone missing.