Sao Paulo, Brazil, has a unique idea for keeping ride-sharing companies in line: skimming some cream from the top. The city has proposed that Uber and others be required to buy government credits to cover their distance traveled. App makers would also have to support a service that picks up multiple passengers headed in the same direction. Uber is happy with the concept. It sees the credit model as "innovative." It would rather pay a small fee than face a ban attempt (as in Rio).