Q: Who earns a living by…

Q: Who earns a living by driving his customers away?
A: A taxi driver.
Jokes, +1:
A policeman pulls a man over for speeding and asks him to get out of the car. After looking the man over the policeman says, "Sir, I couldn't help but notice your eyes are bloodshot. Have you been drinking?" The man gets really indignant and says, "Officer, I couldn't help but notice your eyes are glazed. Have you been eating doughnuts?"