Business people that just aren't that good will exploit you by trying to get you to work for free. Business people that are good will pay you for your work and will multiply that investment as their reward. It's amazing how often the latter is demonized (e.g., Bill Gates getting DOS for roughly $100K) and the former is held up as the ideal person to go into business with (e.g., complementary skills).
I agree. "What you business guys should be thinking about is this: what am I bringing to this business?" Yes. I think some business people way over-estimate the value of their contribution.
(By the way, I found your gender-specific language a little distracting: "business guys" and "man up". Just sayin'.)
http://joshuavolz.com/2010/08/16/business-cofounders-are-a-d...