Living Not-Quite Large

I'm all for a frugal lifestyle, but this 1960ish ad makes a statement that's cause for concern. The claim that the fridge's capacity of 3.1 cubic feet would adequately store a week's worth of food 'for a small family' has me a bit skeptical. Hanging a larger appliance on the wall [!] wouldn't be practical, so perhaps Draconian portion control is the key to this mystery....