A picnic in an outdoor area that is exactly like a regular picnic except that there is the action of marijuana smoking taking place. It is very convenient because it is equipped with smoke ventilation (outdoors) and munchies (the picnic food you pack).
1: Hey, we're having a hippie picnic this weekend in the park, do you want to come?
2: Sure, I'll bring the sandwhiches. And the weed.