Question: Several times in the movie one character is able to ascertain in which hotel room another character is staying simply by asking the front desk for the room number. Was this realistic at the time the movie was made? Today, a hotel would never divulge a guest's room number to a stranger, since such information could potentially be used by burglars and/or predators to gain access to hotel rooms. Was security really that lax in the 1950s?
Question: Why do the kidnappers take Thornhill to the Townsend home and pretend to be Lester Townsend and members of his household? They could have taken him to some obscure place instead, at less risk of being found out.