I just happened to read about Steven Lewis in a Couchsurfing discussion. He was also a member here. There was a fatal road accident in Derby, Texas. This is a nice article about him: http://www.kansas.com/news/local/article83813892.html
Car drivers have selective attention. When scanning the road, they are looking for other cars. Even when they are watching the road, they may not see us. It is hard to imagine, but Steve Lewis and the yellow carrier for his dogs were not noticed by the driver that killed him.