So what you are saying is that the government should between your mind and your body.
although you or i may not agree with what people put into their bodies, "protecting" people from themselves through use of force is inherently immoral. and far be it for us to attempt to stop them through, especialy as these things do no harm to anybody else.
also if its right for the government to tell us we should not do drugs / drink until a certain age. why is it not right to make it illegal for people to eat unhealthy, smoke, not excerise, or even go SKIING (which is a very risky activity)
and unfortunately you are correct; thats not how the world works, everyone likes to interfere with other peoples lives for the sake of "morality". which is exactly why we have the "drug war" which funds criminal organizations by artificialy inflating the price of what would normaly be a dirt cheap commodity. which unlike drug use is not a victimless crime.
the murder victim of a drug related drive by is completely innocent, while someone who has made the choice to destroy his life with drug abuse is not, that was his choice.
btw very mature of you to call me "dumb", really opened my eyes.