Teenagers are programmed to take great risks. Plus they still don't have much of a say in the goings-on of the their life. It's not really their fault.
how can you not believe in natural selection after reading stories like this?
Because there are some extremely insane and misguided individuals in our world that actually believe intoxication is a natural drive to begin with.
Umm have not human beings from the beginning of time been always coming up with some method to get fucked up? Right from wine made out of whatever you can find to mushrooms most cultures have had some kind of intoxicant associated with them. Given the dreary lives that most lead it's a wonder drugs are not a bigger problem then they are.