I am with you. The assumption is that high schools can’t get their hands on it with the current law, which most of us can attest is not true. It just becomes more hidden from parents and leads to more problems. More drunk driving, more fake ids, more crime. It also conditions young people to flaunt the law early on, rather than preparing them to be law-abiding adults.
Same is true as toward pot, FWIW. People pretty much pick and choose which laws they will obey, now. Probably always have.
Put me in the camp that says either lower or abolish the drinking age.