I grew up in a rural Illinois farm area, and each small town still had their small grocery stores. By the early 60's some of the larger towns around began opening supermarkets. Now all those smaller shops have disappeared, people have to travel some ways to visit a supermarket; these towns now have gas/convenience stores, with some basic food items available...
On my 1975 London visit, we stayed in Bloomsbury, in the British Museum area (at the Thanet Hotel on Bedford Place, now a nice place, then a dumpy B&B catering to cheap student groups.
https://thanethotel.co.uk/ ) A new Safeway had just opened nearby and it was considered quite a big deal. It was a purpose - built facility, and laid out in the "US style"...
On her 1957 State Visit to the US, Queen Elizabeth was keen to see an American supermarket...and she did so. She spent time wandering the aisles and chatting with the - astounded! - customers, the date is 19 October 1957:
https://www.routeonefun.com/the-queen-at-west-hyattsvilles-giant-terps-v-tar-heels-game-in-college-park/
"During Queen Elizabeth II and Prince Phillip’s first visit to the United States as a monarch, they managed to catch a Terp’s game against North Carolina and watch them defeat the Tar Heels, 21-7. After the football game, the Queen and her Prince also paid a visit to the former Giant Food Store in West Hyattsville, as “The supermarket, in its awesome majesty, is a growing symbol of American abundance,” wrote one AP reporter covering the Queen’s visit to the store.
According to this Washington Post article:
The royal limousine drew up before the Giant Food Store and, to the complete amazement of hundreds of weekend shoppers, the Queen and her Prince consort got out and walked into the store. Housewives and other shoppers inside the store looked up in astonishment as they found the Queen and Prince Philip peering into their shopping carts. … While the Queen strolled about, the Prince separated from the party and soon found himself munching sample crackers and cheese bits someone offered him. “Good for mice,” he smiled at the gaping crowd around him. The young Queen, clad in a mink coat, appeared charmed by the shopping carts with small seats for youngster. “How nice that you can bring your children along,” Her Majesty told one woman who was wheeling a baby..."
http://cookedbooks.blogspot.com/2011/01/queens-trip-to-american-supermarket.html
"On October 19, 1957, in West Hyattsville, MD, Queen Elizabeth II and Prince Philip paid an unexpected visit to a local supermarket, their first to any American grocery store. The New York Times reported that the royal couple turned into the appropriately named Queenstown shopping mall on the way home from a football game at College Park and wandered into a "giant food store. " The Queen, escorted by the store's manager, looked over the vegetables, "then moved to the dairy food counters where methods of keeping the food chilled were explained." She was, apparently, also intrigued by the meat counter: "The Queen seemed especially interested in chicken wrapped in transparent plastic and looked hard at a large counter filled with steak." Meanwhile, Prince Philip wandered around the store, eating cheese and crackers..."
GM note: the UK had only gotten off of postwar rationing three years earlier, in 1954. Wiki: 'When did food rationing stop? Fourteen years of food rationing in Britain ended at midnight on 4 July 1954, when restrictions on the sale and purchase of meat and bacon were lifted. ..'
Here is a link to a more in - depth article on the Queen's supermarket visit, from The Saskatoon Star - Phoenix [21 October 1957]; she was fascinated by the cut - up chickens "wrapped in cellophane", also that people could select the goods themselves:
https://news.google.com/newspapers?id=n1ljAAAAIBAJ&sjid=N28NAAAAIBAJ&pg=2759,3115824&dq=queen+elizabeth+supermarket&hl=en
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