"People will wave and honk in the street," Gruberg said. "They'll come up to the window and say, 'How can I support you?' A lot of drivers are asking if they can work for the company. Why wouldn't they? Instead of paying $40 to $50 a day for gas, they can be paying $10 to $15." Machen likewise expressed her enthusiasm for the growing fleet.

"[Green Cab] is a business model," she said. "They show the direction the industry is going and the direction San Francisco is going." *

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