This is a stupid argument. Food, water and shelter are considered basic needs for life. I will die if I don't have food or water and am at at a much higher risk of sickness and/or death of homeless.
I've never drank/smoked/used drugs, but I've never heard of this straight edge crap. When I was younger I didn't try them because I'm a Christian and was generally arrogant and condescending. I'm 28 now and still haven't, but don't see any decent reasons to start (and could care less if you do). They won't do anything for my health and I've got better things to spend my money on.
I'm a social worker and I don't think I've ever worked with a client where alcohol and/or drugs have not been a factor at some point. MOST of my clients have been affected by FASD (fetal alcohol spectrum disorder) which is both completely irreversible and completely preventable. People neglect and abuse their kids because of drugs and alcohol. Most domestic violence (men who beat women) happens while under the influence. I'm not saying that happens to most people, but it happens to a lot and I don't want to participate in something that has that kind of affect on so many.