It does exist, it's very popular, and people won't let go, just because the gummint says so. So, the prohibited thing will go underground. It gets more extreme,

It does exist, it's very popular, and people won't let go, just because the gummint says so. So, the prohibited thing will go underground. It gets more extreme, organized criminal activity will increase, people's trust in others and in the establishment weakens. That I'd definitely call a blight on society. Now, which blight we pick is the question. Doing the harmful thing in the open, in controlled ways, or doing it in the dark, in uncontrolled ways? I don't think the latter has much success, if a generally nicer society is the goal.