In an 8.3 N.Y. Times piece about Judd Apatow and David Gordon Green‘s Pineapple Express (Sony, 8.6), writer Mark Harris notes that “pot comedies seem to be flourishing lately, so much so that the genre is subdividing. Those who will always view the Cheech and Chong ouevre (particularly 1978’s Up in Smoke) as archetypal can find their natural heirs in the high-and-higher flavor of the two Harold and Kumar comedies (with a third in the works).”

Harris mentions two or three others, but ignores Curtis Hanson‘s Wonder Boys, which I’ve long considered one of the most aromatic “light stone” pot movies ever made.
Getting ripped has been a standard youth rite since the late ’60s. Every generation of high-school or college-age students has been toking up since, at least on an every-now-and-then basis before growing out of it or deliberately putting it aside because, as anyone who’s ever turned on knows, pot “gets in the way” of having a semi-disciplined, semi-organized, semi-productive life. Still, the only people who have never turned on are the 65-and-older geezer generations, or the ones who grew up in the early 1960s, ’50s, ’40s and ’30s. And even a percentage of them have probably sampled here and there.
The population of the US of A is therefore 85% “experienced” these days, and there is nothing all that wild or provocative or envelope-pushy about pot comedies as a result. They’re funny (i.e., Pineapple Express) but in a “sure, okay, whatever” sort of way. They’ve acquired the taint of normality.