I think the idea that stoned people don't want to do anything is an idea created and perpetrated by the same people who want to keep it illegal. We as a culture subscribe to it at an almost subconscious level. Cannabis doesn't demotivate you, just look at medical users and those in Amsterdam. It's the individual's choice to sit around doing nothing and it certainly seems appealing when high. Though if you notice, the same people who sit around while stoned also sit around sober. It would be a lot more difficult for them to keep profiting off of a nearly harmless plant if their spiel went something like:
"You can do almost everything stoned that you can sober. Even drive and interact in a polite manner with your peers. Studies show that it's not nearly as harmful for you as we once claimed and actually has many benefits, many of which can only be gained by smoking or ingesting the plant. It's still illegal though so don't smoke pot kids. It's for losers."
