Can't do that now. I've told family and friends if they want to just drop in, don't because I won't open the door for them. Call me first. Unless I'm expecting someone, my doors are closed, locked, deadbolted and chained. You aren't coming in.
I grew up the same way. No locked doors, leaving the car running for a quick trip into a convenience store, walking the country roads at night with my sisters. It’s a different world now.