Owning a car during the 1950s in the united states was mostly

A sign of status and success.

Explanation:

During the 1950s, owning a car became a sign of status and success. During this time period, families began to move outside of cities and into the suburbs. Suburbs were designed to be homes for young families that provided more space and better quality than could be found in the cities. However, suburbs were often far from places of work, which made the car necessary. As more people moved into the middle class, a large house in the suburbs, a job in the city, a stay-at-home wife and a car all became signs of status and success.

they required less loading and unloading

explanation:

the shipping container improved shipping because it cut down on unloading time by three weeks, eliminated wasted space, and allowed ships to carry.

i believe it was spain