Weed is NOT that powerful
I don't mean to violate any board rules, but this movie tends to misinterpret the state you get into through smoking weed. By all of the scenes, and Craig's tripping out most of the film.
I've smoked a LOT and the most that happens when you get really high is that you relax. Most people just sit down and are extremely quiet for an hour or so, or they talk a lot about stuff they see. Trees blowing, or rain, for example. But one thing that always bothered me about them getting high is that it turns Smokey and Craig into complete idiots -- who can't focus on anything.
I think that this is done for comedy, but all of their behavior is more akin to that of someone on acid. One of the prime examples is Big Worm's head in the cabinet after he first gets high. Then the statue of the dogs barking inside of his head. Again, its all more like they've done acid that regular weed.
If anyone knows what I'm talking about (experienced what I'm saying), you'd know what I mean.