As we all know, the herb is food, fuel, medicine, clothing, etc. These are the sectors of the economy where the government needs to control in order to stay in power. Marijuana being allowed legally is a direct threat to many businesses and their control on the populace. These corporations pay millions to politicians to keep marijuana illegal. Marijuana is, also, a threat to the military industrial complex.
Alcohol is fine, though.
This battle is too great for the Empire to give up. They have lied too long to back out now and the people are simply too brainwashed. In fact, I see them positioning themselves to set back the marijuana reform movement by decades via these bogus court rulings. The Empire has proven how insanely serious this is for them. They have everything to lose and will not let go.