Correction: Anyone who USES it is an idiot.
Consider the source, Losertarian philosophical insanity.
And so it should be illegal because of that? Heck... people do stupid things with cars every day of the week and no one is calling for them to be banned.
The problems associated with drug use (or any kind of inebriating behavior) can be managed outside of the realm of government. Companies which need workers to be sober can do tests on employees in life-critical jobs and sanction those who fail. There is no need for government to get involved in this at all.
Consider the source, Conservative, Christian, Family man, non-smoker who knows better.