My friends and I were often left overnight by the time we were my DD's age (almost 15). I can definitely remember my best friend and I being alone for a week as sophomores in high school, so 15yo.
Most of the people we know would find that unthinkable now-- or if they did do it, they would almost certainly be furtive about it and hope nobody found out.
Kids can do pretty stupid things no matter how closely adults think that they are watching, so I don't know that this is a completely valid line of reasoning, at least with teens. Oh, sure-- when your 7yo lugs gallons of household chemicals to the sidewalk, you ask questions. I get that. But when your teen offers vague information about where s/he is going to be for the next five or six hours, most parents accept it, ask if s/he has a cell phone, and hope for the best.
The bottom line is that very little can happen overnight that can't also happen during the day and during that five or six hours.
