Interesting article: Income Inequality and the 'Superstar Effect'. I'm a big fan of capitalism but there are some downsides to it. I think this article summarizes it well.
CAPITALISM relies on inequality. Like differences in other prices, pay disparities steer resources — in this case, people — to where they would be most productively employed.
[...] Ultimately, the question is this: How much inequality is necessary? It is true that the nation grew quite fast as inequality soared over the last three decades. Since 1980, the country’s gross domestic product per person has increased about 69 percent, even as the share of income accruing to the richest 1 percent of the population jumped to 36 percent from 22 percent. But the economy grew even faster — 83 percent per capita — from 1951 to 1980, when inequality declined when measured as the share of national income going to the very top of the population.