Ahem. There are neighborhoods in the US where you leave nothing in your car because otherwise your car will become a target. It's often "the rule" in these places that you also leave the doors unlocked because that way "they" won't break your window trying to get in. They open the door, see there's nothing of value to steal and move on. In other places in the US it's (still but fading) normal to leave your car doors unlocked because "everybody knows everybody and no one would steal from each other." Code switching is knowing which of the neighborhoods you are in and how to adapt.