I assume everyone is aware that BMW and M-B use the same outsourced service for the BMW Assist (branded as TeleAid by M-B). When I got my first M-B with the service, it was explained to me that if the car is stolen, you report it to the service, and they will call police with the car location, but not give it you.
Reportedly, the reason is that once upon a time a woman called in her stolen car, and was given the location. In reality, she was tracking her cheating husband. Got photos of him, or something. Divorce, lawsuits, etc, followed. New policy on info distribution shortly after that.