some folks know their abilities and some don't.
I think culture plays a large role. In the US, "adult beverages" are just that we're not raised on them the way many Europeans are. And many, when they reach legal age (or before if they have access) drink to excess. Drinking to get drunk is very common in the US, less so in Europe.
This isn't meant to say Americans are drunkards and Europeans aren't, clearly that not true. What I mean is that European society has a long tradition of drinking in social settings, that the US does not have in the same way.
Just one of the MANY ways our societies are different.