Well I think that depends. In the town I grew up in, you knew there was a stranger at the door if you heard a knock. Everyone else just walked in the house. It is still that way to this day. The UPS and Fed ex guys will open the door and leave packages in the house.

As for the refrigerator, the same thing applies. If you want something help yourself. But again, this is the way I grew up. Small town, everyone knows everyone else. To be honest we were related to literally almost everyone through birth or marriage and the handful of people we weren't related to were such good friends of my parents they were still called Aunt this, Uncle that.

It's not unusual here to find one of my kid's friends sitting in the living room, drinking a soda, eating a snack and using the computer even when the child they're friends with is not at home.

I did have a neighbor take advantage of me and my open door policy some years ago. They were new to the area, came from the city. The area I'm from the stores close ridiculously early and frequently have severe blizzards in the winter. When we did our grocery shopping, you did it so that you could live out of your freezer for several weeks if you had to I even had bread and milk frozen.

Anyway these neighbors decided that it really didn't matter if they made it to the store or not, they'd just come get things from my fridge, cupboard, or pantry. It had already become expensive and annoying. I usually threw what we where having for dinner in the Nesco before work so when we came home we could sit right down to dinner. I overslept one morning so everything I'd planned on cooking for dinner was on the counter and the meat I'd taken out the night before was on the top shelf of the fridge. It was spaghetti so it wasn't that big of a deal cooking it after work, except I came home to discover that the pasta, sauce, meat, garlic bread and even the flipping salad ingredients had disappeared. They even took the dressing for the salad!