steampunkvehicles:
This article at Hemmings points out another factor in creating these wonderful streamlined beer delivery trucks. Prohibition lasted from 1919 to 1933. By the time beer companies were allowed to deliver beer again, all of their delivery trucks would have been at least 24 years old! That meant that everybody went out and built new trucks. Streamlining and art deco was all the rage and companies competed to have the most eye-catching delivery trucks.