Clothes moths feed on various types of fabric, fur, pet food, milk powder, mounted animals, hair, woolen articles, carpet, drapery, etc. They have a preference for dirty clothes. If they have to decide between a sugar-stained tablecloth and a clean shirt, the choice will be clear.
Clothes moths shy away from light. So if you see butterflies congregating around a light source, rest assured: they are not clothes moths.