Exactly. Besides physiological adaptations like resiliant livers, what about mental adaptations? I mean, are drinker-evolved humans more naturally obsessive and careful and self-doubting to compensate for the clumsiness and overconfidence of drink?
I wonder if there is not a social evolution attendant to drunkenness. If people are regularly drunk, it means there is a time set aside for excusable inappropriateness. Daily life can be fairly strict because there is a "playtime" that is wild and unaccountable. People learn to express some parts of themselves -- their negative feelings and maybe their true enthusiasms -- under the cover of drink.
There's also an environmental aspect at play. Italians drink a lot of wine but I have never seen a drunk Italian, not once.
The English, on the other hand, get completely hammered.
The Romans had trouble instilling their calm Mediterranean cafe culture in the gray and frigid binge-drinking north. It's an environmentally inspired culture difference that goes back thousands of years, so it's hard to draw a conclusion about drinking and humans as a whole.