The typical American supermarket of the 1940s was much smaller than the standard food store of later years. Case in point, the circa-1946 Safeway depicted here, which encompassed around 9,000 square feet.
Original drawing from Safeway Stores, Incorporated Annual Report 1946
Graphic from Safeway Stores, Incorporated


By the mid-1950s, the typical American supermarket -such as this Red Owl unit- covered approximately 18,000 square feet.
Drawing from Red Owl Stores, Incorporated Annual Report 1955


A & P's "A Blueprint for the Future," a store design from 1970. The prospective super mart encompassed 29,000 square feet. By the 1980s, a large grocery store might have spanned 40,000 square feet.
Graphic from the Great Atlantic & Pacific Tea Company, Incorporated


A diagram showing the key components of distribution in the Safeway Stores organization.  
Graphic from Safeway Stores, Incorporated Annual Report 1946


While most food retailers relied on other companies for baked goods, dairy products, canned foods and the like, some of the larger concerns -such as A & P and Kroger- maintained their own manufacturing and processing facilities. 
Graphic from The Kroger Company Annual Report 1950 


The Winn & Lovett Grocery Company, a predecessor of Winn-Dixie, built a new warehouse, distribution center and corporate office structure in Jacksonville, Florida. The facility was completed in October 1953.
Drawing from Winn & Lovett Grocery Company, Incorporated Annual Report 1952  


California's Lucky Stores built a large distribution center and warehouse facility in San Leandro. It served thirty-eight stores located in nine Bay Area Counties. These were Alameda, Contra Costa, Monterey, San Mateo, Santa Clara, Sacramento, San Francisco, Sonoma and Stanislaus.
Photo from Lucky Stores, Incorporated Annual Report 1954


In this diagram, we see the service area of 534 First National Stores, the location of the main headquarters (in Somerville, Massachusetts) and the corporation's  administrative and distribution facilities. 
Drawing from First National Stores, Incorporated Annual Report 1959


The Stop & Shop chain, also based in Somerville, built a new dry foods warehouse on 72 acres straddling the cities of Readville and Dedham, Massachusetts. The 465,000 square foot facility was completed in 1960. 
Drawing from Stop & Shop, Incorporated Annual Report 1958 


A view inside one of Stop & Shop's modern warehousing facilities.
Photo from Stop & Shop, Incorporated Annual Report 1964  


One of many distribution centers in the gigantic A & P chain was located in Elmsford, New York.
Photo from The Great Atlantic & Pacific Tea Company, Incorporated Annual Report 1961  


Chicago's National Food Stores built a Gulf States Distribution Center and Warehouse in New Orleans. The facility, servicing Alabama, Louisiana and Mississippi, occupied 23 acres and encompassed 295,000 square feet. A regional office building is seen in the lower right.
Drawing from the National Tea Company Annual Report 1962