I have no problem with people, in general, smoking weed. And I have some acquaintances who are marijuana users whom I would trust more behind the controls of an airplane (when sober) than some of my straight-laced friends.
That said, I think that the OP needs to understand that becoming a pilot requires, in my view, changing one's entire attitude toward engagement with the world. One must become constantly focused on safety, risk management, the minimization of potentially dangerous behaviors, and self-awareness of one's own strengths and weaknesses.
If the OP is just taking for granted that he can smoke pot recreationally and be a safe pilot, I think it's evidence that he's not adopting a safe mindset for aviation. A good pilot is one who removes potentially dangerous practices from his life and is open and honest about himself.
One could well be a marijuana user and a good pilot, I think. But if one is willing to smoke weed without due consideration for the possible physiological consequences, be unconcerned about breaking the law, solicit information about how to avoid detection, and be willing to lie on official documents, then he does not have the right mindset for aviation. That is what makes him a dangerous pilot.