The Relative Affluence of Muslim America

The Economist has an interesting piece on the growing importance of the “Muslim market” in the United States and how companies are adapting to it.  They write:

But a new study by JWT, an advertising agency, points out that the 6m or so Muslims in America are, on average, richer and better educated than the general population. Two-thirds of Muslim households make more than $50,000 a year and a quarter earn over $100,000; the national average is $42,000. Two-thirds of American Muslims have a college degree, compared with less than half of the general population. Muslim families also tend to have more children. So the perception that marketing specifically to Muslims is not worthwhile would appear to be wrong.

This is itself an interesting observation.  In Australia and, to a lesser extent, the United Kingdom, the Muslim community is not necessarily known for its comparative wealth or relatively better education.  So what makes the American Muslim community so different?  Is it that American immigration policy has favoured the educated and affluent from the Muslim world or is there something intrinsic to the American system that has led to this?