There’s a big difference between thinking that a glass of wine with dinner is OK – and that offering a taste of it to one’s own teenager in one’s own home is also OK – and condoning binge drinking, especially by irresponsible/naive college kids.
My children were often offered a taste of wine now and then, with dinner, from the time they were in their early teens. (Like most kids, they didn’t like it, and it took them years to develop any kind of a palate.) Alcohol wasn’t a taboo at home, nor was it glorified: we consider it a fine compliment to food, especially good food (special occasions, etc.) Offering a small amount of wine to my teens was done responsibly, in small amounts, knowing that they wouldn’t be driving/going anywhere that night. My kids had wider exposure to alcohol when visiting their European relatives; again, not surprising, but done under supervision.
We certainly made it clear that drinking outside the home could get them in trouble with the law and that if they were ever caught having been drinking and being anywhere near a vehicle (even as a passenger), they’d loose all their driving privileges. We also taught them how to call a cab, and that we’d pay for the fare once they got home, so that they never had to depend on getting a ride from anyone who was drinking. (Daughter did it once to get home from a party that was out of control.)
I believe this measured, rational approach to alcohol prepared them to handle it responsibly. Both kids thought the binge drinking scene in college was, well, juvenile and somewhat embarrassing.