This is not a law. Instead, it is typically a policy that is observed by motels in order to safeguard themselves.
Motels typically need to worry about people stealing from them, damaging rooms, or committing crimes while on their property. In order to try to protect themselves, motels often ask for the license plate numbers of guests' cars. This serves a number of purposes:
- It can prevent people from using motel parking lots as a place to park for free.
- It can help the motel track down a guest who damages a room or steals from it.
- By asking for license plate numbers, motels can deter criminals from using the motels for criminal activity such as prostitution or drug sales.