People pay money to see a film at the cinema, yet they can't come back the next day to see it again for free. People pay money for software, and cpu time, and

People pay money to see a film at the cinema, yet they can't come back the next day to see it again for free. People pay money for software, and cpu time, and storage space. That's what SL payments get you. People give you money for your time, also intangible.