The gap in the quotation (where the “…” are) is important to note. Of course there have been grocery markets all over the world prior to 1946, as well as butcher shops and so on.
Further, there is nothing wrong with supermarkets. What is interesting is that while marketers programmed the middle classes to pay enormous sums of money for worse and worse food, there were not more people interested in promoting health. Or were there?
Maybe there has always been a huge interest in healthy food- just not in the cities where the socialist public education programs were first so popular. Long-term health is ONLY a concern for people who feel generally safe from threats like warfare and gangs and so on.
I think the “great” delusion of modern people is not that food used to be healthier (which I consider an uncontroversial fact), but that life in 1850 (for instance) was utopian. Sure, there were slaves in the South of the US. Sure, the natives and the citizens were constantly slaughtering each other’s civilians. Sure, their internet connection speeds were a little slower, but at least everyone on the planet had healthy food in abundance… and no one was ever deluded by idealism or perfectionism of any kind.