And an out there suggestion... Are you sure it is your car?
A few years back, a guy came out of the shopping mall shortly before Christmas to find his car stolen. He called the cops, who sent out an APB, but suggested he hang around until after closing to see if his car just wasn't where he thought it was parked. Sure enough, there was his car quite a ways away. Except when he looked in it, he could tell by what was inside that it wasn't his car. A woman was pulled over a couple days later, driving his car. Her key had worked on his car; in the frazzle of getting everything ready for Christmas, she hadn't realized it wasn't her car.