Useless, if you believe that whatever generates monetary value in capitalism is what defines usefulness. To many people who don't dedicate their life to money, rather people who find value in knowledge or culture or something, it's very useful.
And to answer your question, there are employers for everything. Just not enough to make but a select few types of degrees have demand that meets the supply...
What is "usefulness to society"? Why do you think you get to say what is and isn't useful to society? You think that history, archeology, anthropology, etc. are useless?
insisting that capitalism is actually effective at determining the true value/usefulness of things to humanity shows that you haven't surpassed a 5th grade level understanding of capitalism
looking at your comment history i'm actually pretty sure you're just 15 or something and have never had what you think of as a "useful" job...