Hmm, I'm quite surprised. For sure, high levels of alcoholism are correlated with poverty and lack of education. Random study:
"In the weighted model, a one-unit increase in neighborhood poverty at the prior examination was associated with a 86% increase in the odds of binging"
Homes might be disadvantaged by the presence of an alcoholic. A friend of mine came from a home like this- her father spent truly stupendous amounts on alcohol. There was never enough money afterwards.
I'm not sure about the wider population, but the abstainers in the study linked by the article were both "lower SES" and more likely to have had drinking problems in the past.
"In the weighted model, a one-unit increase in neighborhood poverty at the prior examination was associated with a 86% increase in the odds of binging"
http://journals.lww.com/epidem/Abstract/2010/07000/The_Relat...
Anecdotally, all the cases of alcohol abuse I hear about tend to be in disadvantaged homes.