Sorry, but I just have to chime in hear and say something about your phraseology. Alcohol *is* a drug... and a deadly, very addictive one at that (if it is severely abused).

A lot of people forget it is a drug very similar to other drugs, and a particularly dangerous one at that. I guess that is because it happens to be legal (or at least it has been since the laws that made it illegal were changed in the 1930's) and so people somehow think it is "different" then other drugs.
So, that being said, I assume you mean to ask why *illegal* drugs aren't allowed to be discussed.
As far as this thread, alcohol abuse is often seen in the same verses that mention food abuse (gluttony, the topic of this thread) so that particular drug is more "on topic" for this thread. But as far as the rule about no discussion focusing on illegal drugs for the board in general... you're guess is as good as mine. But that is the rule (in my experience). The only reason I've ever been given is that it is because they are illegal. (or at least most of them are... in most states).
I guess if we were in the 1930's we couldn't discuss alcohol either... then again, we couldn't discuss anything b/c we wouldn't have any computers. :laugh: