Weed, Sleep, Lucid dreaming
Smokes weed: Ah yes, I can sleep and have a full 8 hours rest in one go!
Doesn't smoke weed: Oh GoD i caN't stOp tHe AnXIEty PleaSE lEtMeGoTosleeP Aurgh! *Proceeds to hallucinate wildly in 2 hour spurts and awakes in a miserable heap, unable to tell reality from dreams*