Totally not safe. Just don't leave ANYTHING visible in the car. Nothing. Your chances of getting robbed go down if they can't see anything to steal. My car was broken into to get a diaper bag. Another car in the lot wasn't hit. No visible bags, just a bike pump and some clothes. They're looking for valuables and electronics, which are almost always kept in bags. And they are much more active on uncrowded weekdays. Why? They're a bunch of pu$$ys and know they'd get the beatdown of the century if they were caught.