Finance is about marshalling resources and using them to efficiently create a lot more wealth. Since wealth is at minimum the thing that keeps us from working 24/7 on getting enough food to eat, and generally gives us the kind of free time we need to invent AIs, post on message boards, have hobbies, and try to get the hot chicks, it can be quite useful even for a non-wall-street worker. Think of finance as the thing that keeps you from carrying a balance on your credit card or buying lottery tickets as investments.