Do you have any facts to back this up? I just don't think the average marijuana user only uses a single joint in a week. I've known a lot of people who smoke and that amount seems off.
And a lot more people than you'd expect are stoned all day. You just can't tell because they're past the giggling munchies phase of smoking.
I really wish I had better data I could link to you. Just reporting my intuition based on personal experience, and knowing a lot of cannabis users. For obvious reasons, it's not so easy to find good methodically rigorous longitudinal studies of cannabis use.
And a lot more people than you'd expect are stoned all day. You just can't tell because they're past the giggling munchies phase of smoking.