Quote Investigator looks at the history of this quotation: Richard Serra? Carlota Fay Schoolman? Steve Atkins? Tom Johnson? Andrew Lewis? blue_beetle? Tim O’Reilly?
Derek Powazek, editor at the Fray does not agree with BlueBeetle's famous MetaFilter comment: "If you are not paying for it, you're not the customer; you're the product being sold." In a follow up post he suggests an alternative: “If you don’t know how a startup will make money, neither do they.”
blue_beetle gets a call-out - from the OUseful.Info blog.