But in most countries they would be able to drink (especially in a private setting), just not purchase. In Europe for instance less than half a dozen countries have a minimum drinking age for private settings, and a dozen more have an MDA in public (but not private), though for some 16 is enough to drink fermented alcohols (alongside a meal with adults for the UK, regardless for Germany and Austria).
That sentence is everything I was taught to avoid. Props to you.
I like the drug/alcohol metaphor for these things, as a child avoid them, as an adult do your thing as long as you remain sensible.