Where I grew up in the US - Appalachia - in the 1980s and 1990s it was common to not lock your house or car. Crime was rare, murder was non-existent, homelessness didn't exist, and drugs weren't a problem yet. In my neighborhood everybody knew everybody else, all working class types (mixture of middle class and lower middle class mostly), it simply wasn't much of a concern.

Small groups of people with intimacy and a culture of low rates of crime. Violence or crime would make you an immediate outcast.