I think you're misinterpreting Joe Kraus. I've seen him do his "Startup Addict" presentation twice now, once at Startup School and once at a YC dinner, and in neither instance did I come away with the impression that he meant you have to start making money immediately.

The meaning I took from this "business model in beta" statement was, "you have to be willing to admit you don't understand how you're going to make money; be willing to evolve the business model based on what you learn after launch". Which seems entirely consonant with what pg has said.