Can someone explain to me the general idea of taking General Education courses for any type of major?

The idea is that college is not job training. Sure, you have a major, a field you specialize in. But in order to be college educated, you need to be able to read, write, think, do math, and communicate at the college level, no matter what major you choose. Most people end up in jobs that don't directly use their major - they're hired anyway because they have a college education, not because they majored in, say, psychology. A college degree means more than just the field you picked. And that's a good thing, or most people wouldn't be employable. Even majors that are highly employable on their own (engineering, physics, computer science, math) need high level technical writing and interpretation skills that simply are not addressed in the science and math curriculum.