You shouldn't buy anything if you don't have a good idea how you are going to pay for it. If you can afford to buy an education just for the benefit of having one then fine.. more power to you! For most of us that is too much money to spend unless it is an investment towards a future career that can pay for it. That is why a university degree is for career building and not for personal development.
Maybe if people actually looked at the cost of their degree and made responsible economic decisions about how far they are willing to go into debt and what they can expect to make afterwards the demand for non-career building degrees would fall. Maybe then the price would fall until a person could afford to get it just because they are inerested.
"Unless of course, you think that only the wealthy should be able to learn anything about art history..."
No. I think in todays internet enabled age anybody can make themselves an expert in anything if they are willing to do the work. If you want to know about art history... go find out about it! I don't think you are entitled to having someone prepare and teach a series of classes for you just because you want it!