The media belittles pot smokers because they are a silly bunch worthy of ridicule
Carl Sagan is soooo worth the ridicule too. As is Neil deGrass Tyson, Bill Gates, Louis Armstrong, Steve Jobs, Seth McFarlane, Jon Stewart, Bill Maher, Wood Harrelson, well the list just goes on and on. Some of the best Jazz musicians of all time were pot heads.
William Shakespeare, Queen Victoria, George Washington...
Pot doesn't make you stupid or silly. You start that way already. Alcohol makes you stupid and you don't have to start out that way.