I completely agree with you. And people who want to get drunk, underage or not, are still going to find out ways to do so. Hell, I was buying beer from grocery stores when I was 16. There's plenty of places willing to risk getting a fine as well as potential prison sentence just to make some extra cash.
The real kicker is, I live in New York and just a few years ago they also raised the smoking age to 21. Yet, as you mentioned, these same people can go to war abroad for the country but it is illegal for them to have a smoke (at least in New York) or a drink when they come back.
Definitely. There is always gonna be a way for underage people to get alcohol. I totally understand that being in California with the same law for cigarettes. Although I've never smoked one, I would fight until my death for someone to be able to do so if they are able to die for our country.