Sigh...
First off, the only side effect that marijuana is linked to is slight memory problems. Others wise not only has it been proven that its not linked to cancer, IT HELPS. They give marijuana to people suffering lung cancer even. Not only that, that image you showed of a pot smoker, looks a whole hell of a lot more like crack, an ACTUAL bad drug. What really happens is you chill on the couch or bed or whatever and do nothing till you come down. Unless you smoke with jackasses, which everyone knows to get high with only people you trust.
Also, no I don't smoke, but I now a shit load of people who do, of which all have great jobs and live normal lives, one I know even rakes and millions of dollars every year cause he works with computers. The only thing wrong with marijuana is that it makes cheap and strong rope, paper, and cloths, which companies use tons of money by using expensive fabric, causing them to protest pot.
All you are is an uneducated idiot who knows nothing about pot other then the propaganda that the government had spread to fool you. Also, way to rip off Cyanide and Happiness.