What movies have you watched where, after watching it, discouraged you from engaging in certain vices?

What movies have you watched where, after watching it, discouraged you from engaging in certain vices? My example would be Casino. After the scene where Sam "Ace" Rorthstein fired that incompetent casino worker for not being able to spot that cheaters were able to hit a jackpot in fifteen minutes upon playing the slot machines. When Rothstein said those machines were mathematically rigged so it only turns up few hits, gambling easily became one vice I could do without because I know I am not going to win so why bother? When I am at the Indian casino with my family I eat at the buffet. Gluttony is better gambling.