Hm. It's not very realistic, though, is it? I don't think I'd want 12 year olds to be able to walk into a shop and buy vodka, they'd kill themselves.
You could probably stop them without legal bans on underage alcohol sales. In the US, it's unconstitutional to ban the sale of violent video games to minors, but a minor still finds it very difficult to buy them, because consumer pressure led to the industry taking it into its own hands and instituting age controls with financial and contractual penalties for those stores that don't comply. There's no reason something like that wouldn't work with alcohol. At the end of the day, there'd still be places where you could get it anyway, but that's no different to the current situation; before I turned 18, I just bought booze in bulk from the internet.
TBH I think the German system works best, 16 for wine and beer, 18 for spirits.
Yeh, this is what I was going to say. The Swiss have this system too, and I'm not sure but maybe the French? But yeh, this is surely the way forward, you get to experience getting drunk legally at 16 without doing it the way I imagine a lot of people drink properly for the first ever time (and the way I did it)-to go out with a bottle of vodka with some people, sit on floor, and drink until you're sick, because you know nothing about how much you should have, at what point of inhibition you should stop etc.
Lower age of Beer, Cider and Wine (cos' wine is just for dinner parties really...noone gets hammered off wine aged 16) Then age of spirits can stay at 18! That system FTW! Peace out xxx