A strong vocab certainly doesn't hurt, as there seem to be passages, and more commonly answers, that contain extraneous polysyllabic diction solely for the sake of making one's life difficult. Answers may use grandiose words and convoluted syntax just to make people think it's a good choice. It is in these circumstances that knowing more words than the average bear can be helpful, if for no other reason than to allow you to eliminate an answer choice and thereby tip the odds of a successful guess in your favor.
I know saying 'read the economist' is played out, but I think it's sound advice. I just took the mcat yesterday, and there was nothing on it any more difficult than any given E article about the state of Georgian (not the state) labor relations. Reading journals is probably good as well, but doing so limits the scope of the subject matter to which you'll be exposed.
As a side note, I actually thought all the passages (except the myth one, as I detest pompous art/history/religion theorists) to be pretty interesting. The bee one was kind of cool.
