Have you ever noticed that when it comes to drugs, movies dealing with drugs vary with the subject matter. Most films dealing with hard drugs like cocaine and heroine are tragedies.
Alcohol is treated as tragic and comic. I think about The Lost Weekend or Leaving Las Vegas. Comedies about alcohol are Animal House and Strange Brew.
Pictures about pot are almost always comedies. One could say Reefer Madness is a tragedy, but I think of it as a farce: comedy.
Even tobacco is treated as evil when it is the subject matter. The Insider, for example.
How does that reflect on society's view of cannabis? Society at large views pot as funny. Nowhere near the threat the ONDCP would have us believe.