Sometimes I have been in situations in life where I think I must be insane, because everyone else sees something I do not. I got a bit of that feeling reading this article.
But the author does throw around some numbers, with the high water mark being 34,000 people. That's still only around 4% of SF's residents. Not even remotely close to "everyone".
I've never been a part of SF's drug subcultures, so I was never likely to run into these kinds of parties in my time here. I never felt like I was somehow oblivious to everything going on around me.