I like Jordan’s answer. In another words, you’re bored.
To answer your question “Why are we here?” – We’re here to live. But probably this is not the answer that you’re looking for. Your questions are bad formulated, probably unanswerable. “Are we just supposed to work at jobs we don’t like to buy stuff we don’t need?” – If you want yes, if you don’t want then no. – would be my answer and it is probably not what you’re looking for.
When our minds are bored they will create things to act upon real or not real. More intelligent you are, more complex things you’ll create. Finally you’ll start creating paradoxes and unanswerable questions that goes full cycle, are really complex and serves no real purpose in your life, it just keeps your mind busy. This will consume a lot of your time and bring unhappiness.
How do you feel when you’re dueling on those questions? How is your state? For me it used to create stress and take out focus, making me unproductive.
Do you know the Socratic Paradox “I know that I know nothing”? How intelligent this question looks like, you can spend all your life talking about it but there is no point at all, it just goes full cycle. His mind created that argument to prove that he was the wisest man because he knew that he was ignorant while others didn’t. Well, he just proved himself more ignorant than the others also, didn’t he? Invalidating his argument. And we can go on forever…
I think it’s also important to note that every argument that mind can create it can create a counter argument. Everything that I just wrote you can find a way to argue against. It’s the nature of an argument.
Questions are very important but they should serve a purpose. So if the answer of the question can’t be acted upon or it’s not beneficial it doesn’t deserve my attention. That’s how I’m sharpening my logic.