I think it's a direct representation of how unequal the power in society is. Being the 10th wife of a price is better than being the first wife of a commoner s

I think it's a direct representation of how unequal the power in society is. Being the 10th wife of a price is better than being the first wife of a commoner somewhere like Saudi Arabia (as an example - can pick any society with high power inequality) in terms of the chances of reproductive success of your offspring.