Continuity mistake: Gene Wilder's pencil disappears in the classroom scene. (00:33:30)
Continuity mistake: When Harry says the word to trigger the bull, the bull runs out at him and has horns. But in another shot later, the "bull" seems to have become a cow (with no horns).
Continuity mistake: The first time Skip meets Meredith, and Meredith announces her intention to get a job at the strip club, this part has obviously been added later as an explanatory afterthought and is not well integrated: the lighting, audio and Williams' demeanour do not match the rest of the scene.
Chosen answer: Because his employers discovered he had put grass (marijuana) in the salad and got all the dinner guests high. Well, he didn't, the cook did. But he brought it into the house so he was fired.