To answer the OP: I think everyone would agree there is quite a bit of drinking and
boating on
charter boats. For most people that is a
vacation, booze seems to go along...
Not sure to the extent of drinking while
boating with liveaboards. But once you're anchored or docked securely, who cares what people do really.
Whether more sailors drink overall more or less than other sporting demographics is moot and not worth the debate IMO.