It's common in Bangkok for the hotel to take the ID cards of young women who accompany guests up to the room at night, or who want to visit the guest. The cards are returned to the visitors when they leave. At SGS, an unaccompanied visitor must wait while the hotel guest is called on the phone to verify that the visitor is expected and welcome. If the visitor is identified by the hotel guest on the phone, the hotel often does not confiscate the visitor's ID. This rule was also applied to my attorney (a young lady), who has been to the SGS meet with me several times, but has to wait each time while staff telephones me. I have no problems with the policy, -- IMO it contributes greatly to security.