To every person who said "I don't need subject XYZ to work in field ABC", I say, you are a fraking idiot.
For many of the classes people take, it's NOT the content, it's the process of learning. Just as athletes do all kinds of exercises and training to prepare to compete in sport X, 'brain workers' need to exercise and develop their brain to prepare to be an expert at Z. Be it Organic Chemistry, Calculus, English Literature, Latin, History of Japan, etc, etc, it's the mental exercise of mastering the material, NOT the material itself that is essential.
I don't want a Doctor or Lawyer or EE or whatever who hasn't sufficiently built up mental muscle power to cure me, represent me, or design the equipment that saves my life.