The hoi polloi got to travel in Pullman Cars. Actually this is a first class car so we've got a better class of hoi polloi here.
This is the Pullman Topaz parlor car (1913). It resides in Station Hall, a large area to the left of the museum entrance. The hall mimics a railway station and contains whole trains which include locomotives and various cars such as the Pullmans and the royalty cars. If you want a panoramic view, click here.
In Britain, luxury lounge cars were called Pullman cars after the American company of the same name.