Should all college courses be related to your future occupation?

As a college student with the goal of one day becoming a doctor, I find myself strategically selecting the courses I will need for this future career. However, after reviewing many schools' course requirements for this field of study, I begin to wonder why we must take all of the classes they require. The countless Literature, History, and Math classes we must take tend to be somewhat irrelevant.
Many students go in to school knowing exactly what they want to do with the rest of their life, yet they must go through four years of college, studying completely irrelevant subjects, that more than likely will never be used again. We should not be required to spend countless hours studying, and even years of schooling, on top of all the money for tuition, to take classes unrelated to what our major focus is. Rather, we should spend more time focusing on what we plan to have a career in.
I have argued this with many adults, who tell me that colleges require you to take these core classes so we will have a basic knowledge of these subjects. But I'd like to argue that we gain the basics in high school classes. Why repeat this at such a high cost to the wallet? My senior year in high school was a total waste of time because I have basically gone over the exact same thing my first year in college. Instead of wasting my time retaking courses I have already taken, I should be devoting my time learning new material.
If colleges adopted this new standard then the chances are more people would want to attend college and get a better education instead of skipping out on it and starting a career right out of high school. This would promote a more knowledgeable society who are not blanketed by ignorance.