The wartime economy required cooperation from workers and industry.
Explanation:
During the war, the economy was transformed in various ways, and the government wanted to find ways in which people would not be affected so deeply by it. One of the ways in which the government was able to somewhat control these changes was by asking both workers and the industry to cooperate with the war effort. This was done by controlling wages and prices. This ensured that wages and prices remained at a sustainable level throughout the war.
"There ain't no such thing as a free lunch" expresses the idea that even if something seems like it is free, there is always a cost, no matter how indirect or hidden.