To people who take drugs: Is that temporary high really worth the hangovers and health problems later on?
if I did anything that had those effects, probably not.
Kids like the ones you mentioned are just trying to be trendy. They don't actually get anything from what they consume, be it music, drugs, whatever - they just want to brag about it the next day. Some people make the assumption that this way of acting is all a fleeting attempt to attain sex, but even sex is just about bragging rights. When your friend start smoking weed they'll probably be the type that have no concept of conservation, because they don't care about getting high, they'd rather brag about putting a half ounce in a single blunt. Kids like that don't even inhale.