Alcohol. People have a drink to celebrate, but also drink to hide their shame. Lastly, drunk driving is a crime.
A mask is also a valid answer. They can be used to celebrate Halloween or at dress-up parties, a mask can hide your shame and masks are used by thieves.
Update: This one has more valid answers than I thought. Money, drugs and night also work.
A man dove into the water with no tank, snorkel or any other device to allow him to breathe, yet he stayed down there to live for the rest of his life. How is this possible?
Two scruffy dogs were walking down the street. The first dog turned to the other and said, “Do you realize that if one of your fleas jumped onto me we would have the same number of fleas?” The second replied, “Yes, but if one of your fleas jumped onto me I would have five times as many fleas as you.” How many fleas are on each dog to begin with?