This style was popular during the great depression among hobos and ramblers. It was a real quick and cheap shave at the barbershop. Down in the South during the 1920’s when business was slow barbershops would have group deals for the hobos and tramps. For a nickel or in exchange for sweeping the floor they could get a quick shave and an un-styled rectangular “boxcar” stache. The name comes from the shape and the clientele.