It seems like there are three fundamental business models for tech startups right now, the first and most profitable being to impose oneself as the middleman in

It seems like there are three fundamental business models for tech startups right now, the first and most profitable being to impose oneself as the middleman in a real money transaction, the second and less profitable one being reselling AWS services with some frosting, and the last being the word "...ads?" scrawled on a cocktail napkin. Seems like most tend to go for the last one.