Drugs are very fun but, many times, can lead to a false circle of friendship. Depending on how deep you are, you end up surrounding yourself with super shady people who you would never trust/hang out with normally but the lifestyle keeps you together. Eventually, you believe that your little circle of “friends” are the normal ones and everyone else is screwed up.
This is the whole problem; not everyone agrees. I don't care if other people want to drink or use drugs, but don't want to. When it expected in a professional setting, that becomes problematic.