Come check out our poster collection at the State Library! We have recently added a number of World War II era posters that focus on how the war effort had major effects on the home front. Growing your own food and canning it was seen as an important contribution to the war effort, as well as to ensuring civilians maintained a healthy diet in the face of rationing. http://azmemory.azlibrary.gov/cdm/singleitem/collection/posterswwii/id/2/rec/3
During WWI home cooks found the power to prolong the surplus from their victory gardens through canning, allowing commercial goods to be distributed to the army. Likewise, the depression of the 1930s and WWII also gave home cooks a reason to preserve their homegrown food.
There was a time in this country when there wasn’t a supermarket within a convenient drive from just about wherever you might find yourself (unless you choose to live out in the middle of nowhere, then that’s on you). There was a time, particularly in the South, when people produced almost all the food they were going to eat for the year during the growing season. They then found ways to preserve the bounty and subsisted almost solely on the abundance during the lean months.