>>213403737
IMO it's either based on the fact that some of the food looks rather plain and unadorned, or some of the less aesthetic foods from the early 20th century. A lot of that food is still delicious, but it doesn't look particularly pleasing. Pic related, fish balls.
>>213403788
No, it's mashed rutabaga. Some people puree it nowadays, but traditionally it's supposed to be mashed.