A study reported in the LA Times suggested that Chantix appears to reduce the desire for alcohol as well as for smoking (see "Anti-smoking drug may curb drinking, too").
Now, there are many people out there who probably drink too much alcohol and should curb their drinking, such as the young lady in the poster shown below. I suspect, however, they would not voluntarily opt to take any drug that cut their desire for alcohol.
But don't underestimate the power of marketing! Some day we may see Chantix TV ads that feature drinkers who look just like you or me suffering from a "problem." Although they may be having a great time at bars and parties, they secretly wish they did not have all those margaritas, beers, or martinis! Chantix to the rescue! Cut to sober tortoise winning the race against the inebriated hare!
Maybe Pfizer would lobby state legislatures to require teenagers convicted of DUI to undergo Chantix treatment. I think more people would be OK with that. Teenagers may like the hallucinogenic side effects too!
Just some random thoughts!