Why is it that virtually every culture in human history used a mind-altering drug? I think the natives of Northern Canada are the only ones who didn't have access to such a drug.
But be it nicotine/pituri, cocaine, caffeine, khat, cannabis, magic mushrooms, opium, alcohol, DMT.... EVERY culture found them and used them. It seems inherent within all of the higher species. Dolphins get high off puffer fish, elephants will drink alcohol (without induction) and raindeer eat mushrooms they KNOW will make them trip. If one individual discovers it, they all seem to learn.
Is it a flaw or part of the design?