not that simple...
Yes, alcohol does have a bit less than 7 cal. / gm, and yes they are empty calories. But the question of how the body uses those calories are still debated.
I always wondered why alcohol is not listed on nutrition information labels along with fat, protein, & carbs. I did a search on alcohol and found that researchers still debate the calorie effect, because although alcohol has about 7cal. gm, some argue that this is completely offset by the rise in body temperature created by alcohol.
I for one can state from experience that there have been many nights that I've had to have a fan blowing directly on me in order to get to sleep because a night of heavy drinking left me feeling hot & sweaty.