I hate to jump into someone else's conversation, but I will anyway. Refining oil is a manufacturing process. You take a raw material (crude oil) and process it into a finished product (gasoline, kerosene, and other chemical products), and that is the essence of manufacturing in nut shell.
I agree that refining is manufacturing, and so does the original poster. But what about my follow-up question: Do the engineers who design the refinery also create wealth?
(By the way, please feel free to jump in at any timethese are very public conversations.)