Jade mocking Robbie for being a vegan is ironic (and likely intentional) give that Elizabeth Gillies is herself a vegan.

The entirety of this episode is a parody of the 1985 film The Breakfast Club, down to virtually every scene being a recreation from the film. This is rather risqué given the target audience for the show, as the film covers mature subject matter. For example the "vegan" talk is a substitute for a discussion of virginity and the scene were the kids are eating hot sauce replicates the scene where the kids in the film smoke a joint.