@Frank Apisa,
Hmm...
I think age restrictions for lots of activities make sense. Voting, driving, tobacco use, and being served alcohol in public places. It gets tricky, however, with consuming alcohol or drugs at home, even under parental supervision. There are health concerns and in really dysfunctional families, the safety of children to consider. And, what about parental determination for vaccinations? I think there are already too many religious exemptions, enough to threaten public health.
I don't know where to come down on this question, Frank. I'm glad the responsibility for these types of decisions is not in my hands, even if I can find reasons to disagree on a case-to-case basis.