You raise a very good point, and after thinking about it I tend to agree. Lots of folks including myself have often criticized the "useless" courses offered by universities such as leisure studies or early Mesopotamian history since there's little relevance to any job that one is likely to hold after graduation. As you pointed out this would be looking at it from the investment & business point of view, as in what does one get in return for taking those courses?
But if we view education as a pure learning experience where students can learn about things which they'd otherwise never be exposed to, well, that changes a lot of things doesn't it? Universities usually have large archives of rare books, music, papers, and other materials along with researchers & staff with deep, specialized knowledge in all kinds of esoteric subjects, it's a giant collection of knowledge along with the people who can make sense of it and teach it to others. If I want to learn about the history of Ukrainian folk dances or how magnets really work, there's gonna be someone at my local University who's an expert on that stuff and can teach it to me and help guide me on my journey of discovery.
Once again, thanks for your post, and thank you for reminding us what learning & education is really about.