Well, generally speaking, there are two reasons people will wear sunglasses. The first one is that he wants to protect his eyes. As we know that sunglasses are designed for people who like doing activities outdoor. By wearing sunglasses, it can protect your eyes from the UV rays and strong sun light. Also, it can avoid some eye infection. On the other hand, he maybe wants to look cool and fashionable by wearing them. Nowadays, there are many famous stars who do not have any vision problem, but they still wear sunglasses to make them look cool. This is a new fashion.