> As wealth accumulates at the upper end of the income spectrum, it has a self-reinforcing and accelerating feedback effect: greater wealth purchases greater political and social influence, which enables even greater wealth production, often at the expense of the poor and the less wealthy.

A case for wealth accumulating on top can be made, if you believe wealthy individuals, on average, are better at allocating funds for a given "common good objective" than the government. In that case you would expect them to be more intelligent and benevolent in their allocation of this wealth as well as less susceptible to corruption (financial, moral, ideological) than the bureaucracy.