Especially when we are being bombarded with propaganda that something is "harmless".
Alcohol is something that we know is harmful in excess. We have been both told and shown that repeatedly.
But if you try to tell someone that too much weed is bad for you they automatically will come back with "that is just propaganda."
They will continue to say that as they lose their job, are given an allowance like a child because they have run up major debt, and their wife of nineteen years is thinking about leaving because they can not even be trusted to watch the children while she is at work.
I've never been bombarded - and I live in a state that recently legalized.