As far as i can tell the reasons for economic inequality up to this point in history are due to the fact we just dont know how to have a functional system with economic equality.
Please dont get confused by some kind of philosophical equality because there will always be a difference between people i know but it seems one day we will have some kind of economic equality right?
Does anyone have a good reason to want to keep economic inequality?
It even occurs in nature, worker ants queen ant etc.
What you should be concerned about is oligarchies, the words economic-inequality only exist because it's at the top of it's foundation in the existence/result of manifested meaning.