First, you should stop quoting pg's essays as though they were infallible sources of truth. It's not helping your argument. I like some of his essays; others are misleading or dead wrong (for example: http://idlewords.com/2005/04/dabblers_and_blowhards.htm). Empirical evidence always beats philosophical pondering; shawn-furyan provided data that pg was wrong, and you did nothing but post another data-free essay.

Second, you should stop assuming your ideological opponents are idiots who don't understand simple concepts like growth of wealth. We do; of course it is possible to "grow the pie". But since the 1970's, the majority of GDP growth has translated to income gains only for the top decile. And in such a regime, why should everyone else bother to grow the pie? What income inequality has done is create people who make a rational, and perfectly valid, calculation that "growth" is pointless and not worth fighting for, since they won't see any of it.