Heavy Drinkers Are Heavy Drinkers

According to UNCLE JOHN'S BATHROOM READER Moderately drinkers. on the average, earn 7% higher than non-drinkers.

I think this speaks for itself, literally.

A little alcohol in ones system tends to loosen one's tongue.  When they have a few drinks in  them  they get witty and  even become philosophers..... which sometimes both are mistaken for smartness.
Smartness = higher pay.

Notice  the Uncle John pointed out "MODERATE DRINKERS". Heavy drinkers make a fool of themselves almost  every time.