Re: Why do moths eat clothes?

Adult moths do not eat clothing and even the larvae are generally 
restricted to products of animal origin- hairs, wool, feathers, bristles, 
furs, silk, leather or felt. Like the carpet beetles, these larvae gain 
protein (in the form of the nearly indigestible keratin) from animal 
fibers and this allows them to grow and eventually metamorphose into adult 
moths, which then reproduce and die. The adult moths do not feed, but 
often serve as evidence of the larval activity as they fly up when 
disturbed.  Cedar chests and mothballs are often used to keep them out of 
woolens and furs. The clothes moths belong to the family Tineidae.

References:

Berenbaum, M. R. 1989. Ninety-nine Gnats, Nits, and Nibblers.  University 
of Illinois Press, Urbana.  

Borrer, D. J., C. A. Triplehorn and N. F. Johnson. 1989. An Introduction 
to the Study of Insects.  Saunders College Publishing, Philadelphia.

Davidson, R. H., and W. F. Lyon. 1987.  Insect Pests of Farm, Garden, and 
Orchard. John Wiley & Sons, New York.