A film which preys on the natural tendency for stoners/slackers to want to watch other stoners/slackers do things that they themselves would probably do in the same situation.
Pineapple Express is total slaxploitation in that the folks that made that movie knew they could make money off me because I'm a fuckin' slacker and so are the funny dudes in that fuckin' movie, therefore I HAD to watch it and laugh my ass off.