The reason they couldn't get a room is that there were no staff. In the craziest census of all time everyone had had to return to the town of their birth. The Chief Receptionist had gone to Bethany and the Head Chambermaid to Capernaum. It so happens that the Manager was born in Nazareth, so Mary and Joe had passed him on the way without realising it. When people arrived at their home towns there were no shops or services for the same reasons. There was chaos and the papers were full of it at the time, especially the Bethlehem Star.