Alcohol kills more people than most other drugs combined. But, it has no clear upper or downer affect, unlike other drugs. Alcohol works to accentuate your moods, so a happy person would be happier if they were to drink. Whereas weed is a downer, smoking weed makes you feel depressed, it has some good side effects, but so does being stung by a wasp, so that doesn't count for much.
IMO both are pointless, weed makes you slow and lethargic, I have never known an energetic weed smoker, and alcohol makes you clumsy and forgetful. So, I don't touch either, and I find it pathetic when people need either of them to have a good time. I used to drink, but I find all alcoholic drinks taste horrible and I have never touched weed because it smells. I've had pot cakes and been with people in a hotbox though - but these had no affect on me.