They want two things: Your address and the garage door opener.
The registration of an envelope can provide your home address. The garage door opener let’s them into the house.
It is easy to know where you live if your car is left unlocked, even while at the mall. This is why I say never leave your garage door opener in the car while parked outside at night or even during the day if in the driveway and unlocked. Thieves are getting extremely smart about putting two and two together.
Registration plus garage door opener = easy access.
Here is a story from Polk County Iowa Crimestoppers
1/12/2014 - Garage Door Openers Used for Local Burglaries
The Des Moines Police Department is investigating six cases of burglaries to vehicles where remote garage door openers and vehicle registrations were taken. Some of these victims have gone back to their residences and found those burglarized as well. There is a possibility these 6 cases are connected.
Possible considerations to help prevent these crimes include removing from your car, the garage door opener and items with your home address on them. While you are required to carry your vehicles registration with you while driving, it is easily placed on your person once you leave your vehicle. Another option would be to store the vehicle registration in a less obvious location than the glove box.
Anyone with information on these crimes is asked to contact the Des Moines Police Detective Bureau at 515-283-4864 or anonymously to the Polk County Crime Stoppers at 515-223-1400.