Wow...didn't know I was going to generate such debate. That's good.
My parents were not heavy drinkers and their attitude towards alcohol was very open. If I was 15 and wanted a beer, I could have had one without any problems. Thing is, I didn't want one because there was nothing secret or taboo or exciting about it. That's the way my father was raised, the way I was raised and the way my kids will be raised. I think the big problems come when young people are "turned loose" for the first time at a party or at college and abuse alcohol because its been forbidden and they can't handle the freedom.
Plus, I'm pretty sure my kids will see beer as a craft beverage to be savoured and enjoyed on its own merits and not a means to an end like some kids. I didn't drink at all in high school because as I said, I didn't see the big deal but when I did start drinking beer in college, it was craft beer or micro-brewery beer because I liked the beer, not the buzz.
Not to get into a political debate but the US attitude towards drinking age has always confused me a bit. Here you can legally drink at 19 (18 in some provinces). I never understood how someone can be asked to vote or go off and die for their country but they aren't considered old enough to have a beer.