The definition of want here is ambiguous, and that makes this is a little hard to parse. How are you defining "want" with respect to "utility function"? Do you mean to make them equivalent?

If by "want" you mean desire in accord with their appropriately calibrated utility functions, then, well, sure. A friend is selfish by any common understanding if he doesn't care about his buddies' needs.

Assuming that the utility monster is not, somehow, mistaken regarding it's wants...