An alternative explanation for this association was given in a 2005 publication.
We conclude that most likely the positive association between drinking and earnings is the result of the fact that ethanol is a normal commodity, the consumption of which increases with income, rather than an elixer that enhances productivity.Increased income leads to more social drinking not the other way around.
The 2005 study was publish by the National Bureau of Economic Research which according to their web site is a "non-partisan research organization" which disseminates "unbiased economic research among public policymakers, business professionals, and the academic community." The other study was published by the libertarian Reason Foundation which is an anti-tax group. The Reason Foundation uses the study to argue against excise taxes on alcohol. Without making a detailed comparison of the two studies which one has would have more credibility for you? I can tell that for me it is 2005 study.
Now there is a funny thing about the two studies, Bethany L. Peters is an author on both of them. Despite this fact, the Reason Foundation report, which was written after the 2005 paper, does not reference the 2005 paper. This illustrates how scholars can alter their research findings to fit the ideas of their patrons and why the commercialization of academic research is so problematic. However, that is a topic for another post.
In closing, I would like to say to Graham, you reap what you sow. You spin, lie, boast, rationalize, and take anti-intellectual postures, soon enough Penn State students are following along.