One significant difference between WW1 and WW2, at least in the US -- the country realigned itself for wartime in a way it did not the first time around. You had women entering the workforce in ways they did not during WW1, which meant you had some families earning dual incomes. At the same time, the US instituted a rationing scheme, so even though households were earning more money, they couldn't spend as much.

Two other significant differences: the GI bill for returning vets (which made it significantly easier for them to get higher education) and the rise of automobiles (which in turn unlocked suburbs and mass home ownership) gave households somewhere useful to put their money.