The most aggravating things about being a driver 20. People who show a lot of money and don't tip. You might not be aware of this, but when you search for cash at the door, the driver can see into your wallet or purse. We know what you have. Other customers are more obvious. They hold a money clip in their hand. There are people who show over $500 in 10s, 20s, and 50s. Flipping through the money clip for twenty seconds, they pull out a bill or two. It shows they can clearly tip. It's inexcusable to show the driver how rich you are when you don't tip. Last updated: August 8, 2008