They are certainly related questions—but I the answers to the questions may be different. But what the protestors demand might be different than why they are protesting. (As you point out, Marx has a lot of useful insight on this front and whether or not you like Marx’s thesis, I think it’s important to read Marx to at least be aware of what he actually wrote.) We need to identify the root problems and address them.
The folks marching in the street have shown anybody who didn’t already know it, that we have some serious problems. We need to address the problems. By we I mean all of us. The need to identify and solve the problems remains whether or not we agree with any particular list of demands put forward by any Occupy group.
I’m more concerned with what the problem is than what Occupy Wall Street thinks the problem is. (Granted, in many cases, I think Occupy has hit the nail on the head.) I want to get past “what do these weird kids want” to focus on “what do we need to do to solve these problems.”