I have a thought:
The positive correlation between atheism and higher education and the negative one between atheism and divorce, incarceration, and abortion rates may be because atheists don't settle for as much less as theists do (on average). In support, atheists have, as we see from their being atheists, not settled for so much less than they could have with regard to their own cognitive processes where such cognition regards deities. They haven't settled for less than consistency in their beliefs.
As such, atheism, general non-belief, giving into one's hunger for knowledge (for those who have such), and generally not getting into commitments without a nice examination of how it will affect one's life are all the byproducts of simply not "settling for less".