Most of human culture and philosophy evolved during these periods and bakes in the idea that the pie is finite and that anyone with more of it has stolen it, because that was just an accurate picture of reality.
A growing pie is a rare condition. It has happened a few times during periods of high civilization: Egypt, Greece, and Rome in the West and similar examples exist in lots of other places.
A rapidly growing pie is entirely new. The modern world is an extreme historical aberration built on the scientific method, modern engineering methods, and the discovery of massive amounts of exploitable cheap energy in the form of first fossil fuels, then nuclear power, then (today) learning to exploit things like solar and wind energy at exponentially larger scales. Other innovations that have fed into this unique condition include synthetic fertilizers, antibiotics, vaccines, etc.
Humans have never lived in an environment like this. Everything in our evolution and our accumulated culture is screaming that it's wrong -- that it will either collapse tomorrow (hence the perennial popularity of doomerism) or that it must be built on some kind of insanely massive crime because otherwise where is all this wealth coming from? That's because it's impossible. It cannot be. The idea that wealth can be created at this scale is just... not a thing that has ever existed until maybe 200 years ago max but really more like 80-100. Before that there was only subsistence and theft.
Edit: I'm not arguing that there is no slavery or near-slavery or theft/conquest in the modern world. These things certainly still happen. I'm arguing that it is not the primary source of our massive wealth. Slavery and conquest have always been around and no society has ever been this wealthy or grown this fast. Not even close.