In addition to granting food, the Chief can do anything regular Villagers can. Since he doesn't do work, it saves the time of your workers if you have the Chief do these things:

Heal the sick.
Gather herbs.
Make the potions.

Your chief can also get pregnant (if female)

This is good since she can't work anyway, but don't do this if you are short of food & need her to make magic food.