Study: Drinkers Earn More Money Than Nondrinkers
Social drinkers who hang out in bars bring home even bigger paychecks

Why? Networking, networking, networking!! Whether it is a good or bad thing depends on who you talk to, but business is all about who you know. People with connections up the yin-yang tend to do very well financially! Heard about the study here. Great quote below from the actual report-

Our empirical results support the hypothesis that drinking improves earnings by increasing social capital. Table 1 presents the descriptive statistics: The average male drinker earns 21 percent more than the average male abstainer, and the average female drinker earns 8 percent more than the average female abstainer. Among full-time workers7 the average male drinker earns 19 percent more than the average male abstainer, and the average female drinker earns 23 percent more than the average female abstainer. The econometrics control for differences in demographics and personal characteristics in each group

http://www.reason.org/
http://www.reason.org/pb44.pdf