I personally,whether i am mad or not is highly debatable lol,believe that they are afraid of independent thinkers which would undermine their control system and cause people to ask them to many questions that they do not want to answer.
Also marijuana makes you care more about issues of justice and also helps to make most people care more about the state of our planet,this is also not something that they want,which is why beer is legal and weed is not,after 10 pints you will not give a shit about the planet or anyone or anything else,not to mention that you will become addicted to beer and have to work all week to buy some more.
So to sum up i think they want to keep people drunk,dumber,careless and working in shit jobs and marijuana would make this much more difficult for them.
This is just my opinion though and i may be completely wrong
