During Mardi Gras costumes are usually only worn by people in parades or when going to parties. However on Fat Tuesday everyone is encouraged to wear a costume or mask. Most banks in New Orleans are closed and if you do visit a security conscious area expect them to ask you to remove your mask. While many people wear rented costumes the most sought after costumes are the unique and individual hand made one. Much like royalty no one wants to be seen in the same costume twice.