Pharoah, and all his subjects. That’s a lot of weed.
Now I’m not saying I believe what this guy is saying, but in direct response to your question, wheat, the primary source of nutrition for all of the Middle East at that time is susceptible to a fungus called ergot which produces and alkaloid very closely related to lysergic acid. So if this was occurring, then mass hallucination is not beyond the realm of possibility.