Paradoxically we do know a lot more about some of the ancient Near Eastern societies than most states that preceded or succeeded them. There are still thousands of clay tablets which nobody really had time to read, while pretty much all Roman and Greek texts (and effectively all administrative documents) that weren’t copied during the middle ages are lost.

> provinces and basically amounted to plunder.

Also redistribution. The mid/late Roman state spent had huge taxes and spent almost all of it paying for its professional army almost all of which was stationed in the provinces.

As a consequence the Roman economy was highly monetized, long distance trade was widespread and different regions economically interdependent which again seems rather modern.

Also when talking about “plunder” in the ancient world it's almost entirely slaves not gold/silver or moveable goods. That had mostly dried up during the imperial period.