The normal way to explain the phenomenon of an egalitarian society that has extremes of wealth and poverty normally found only in the Third World is to point out that equality of opportunity does not mean equality of outcome. All men are created equal, but do not apply their god-given talents equally. Gods and clods, in other words. Of course being created equal does not mean an equality of talents, since some people are born more intelligent, healthy, good-looking and so on. It seems merely to amount to equality before the law, a principle which had been established in Britain long before the American colonies broke away.
Equality of opportunity is a nice idea, but means little.
A cripple has an equal opportunity to run a mile as a trained athlete, but that's no great compensation.