Or, just don't pass laws that impinge on people's freedom and privacy.

It really is that simple.

Not that I agree with the parent comment but this is pretty much the only thing that laws do. If you start with the assumption that something is legal and only think differently when there's a law that says it's not, then you're not too far off from the practical reality.

So you're against minimum drinking age laws?

I definitely was not aware America was a country where i need to be permitted my actions and otherwise kept on a registry of who's allowed to do what.

That's how alcohol works. It's how cigarettes work. It's even how prescription medicine works.

Well, now you know.