Because I don't have anything in my pickup worth stealing I always leave it unlocked. They might make a mess but, aren't going to find anything to take. Besides, vehicles are built so cheap now that there isn't even a place to put the key in the passenger side door to unlock it. So when I come out of the store , if the truck is locked, I always have to walk to the driver side to open the door and then back to the passenger side to put in my groceries. It's such a pain I started leaving the doors unlocked.