This sounds a bit like Willard Hawkins' short story "The Dwindling Sphere," originally published in Astounding Science Fiction in March of 1940. The story was an early example of ecological science fiction. The technological conceit is that a small group of engineer/scientists have discovered a matter-transmutation process—somewhat like the replicator technology on Star Trek—with the property that the mass of the new object is always less that mass of the raw material used to produce it.
It is very puzzling, for the fact remains that the lump has been reduced to a fraction of its original weight and size. There is, after all, only one possible answer: the greater part of its mass must have been converted into energy. The question, then, is what became, of the energy?
The technology rapidly becomes a defining process of human civilization:
Actually, the discovery appears to have been an accident. Frank Baxter took no interest in its development—regarded it as of little account. Think of it! An invention more revolutionary than the discovery of fire, yet its inventor failed entirely to grasp its importance! To the end of his days it was to him merely a by‑product.
The story is told as a series of journal entries from descendants of the inventor of the matter-transformation process across the years and millennia. In the final entry, the size of the moon relative to the earth is mentioned:
I have no doubt he will return later with some other fantastic delusion. On one occasion it was the legend that, instead of being twin planets, our earth and Luna were at one time of differing sizes, and that Luna revolved around the earth as some of the distant moons revolve around their primaries. This theory has been thoroughly discredited. It is true that there is a reduction of the earth's mass every time we scrape its surface to produce according to our needs; but it is incredible that the earth could ever have been several times the size of its companion planet, as these imaginative theorists would have us believe.
And indeed there were resource wars over dirt:
The Eighty Years' War is over... Chief among the basic causes, of course, were the disputes, between adjoining districts over the right to extend their conversion pits beyond certain boundaries.
"The Dwindling Sphere" has appeared in several anthologies, including Isaac Asimov Presents The Great SF Stories 2 (1940), edited by Isaac Asimov, 18 Greatest Science Fiction Stories edited by Lawrence Jannifer, and others.
A good read, and I remember it frequently...