THE ONE THING I REALLY HATE ABOUT CAB DRIVERS IN SAN FRANCISCO IS TIPPING THEM. NOT SO MUCH THE MONEY PART (THOUGH THAT'S SOME OF IT), BUT MORE FOR THE FACT THAT THEY NEVER APPRECIATE HOW MUCH YOU GIVE THEM. YOU CAN GIVE THEM $5 OR $.50 AND THEY ALWAYS THANK YOU JUST THE SAME ... SHEEPISHLY.