another use is to make non important npcs. aust npcs can be very silly, stupid, or all around annoying because they will almost always have nothing to do with the games plot. they often serve as comic relieve, and are usually beaten up or killed by players and monsters alike.
(dm) you are in town, talking to the inns keeper
(player) alright, we want to stay in your inn mister... whats his name?
(dm) uh, its aust
(player) well, we need someone to show us where the ruins are, so i hired this guy
9aust) yeah, hey everyone, we're goin on an adventure yay! i hope im not eaten by a bear...
Player one: we are here to restock are supplies and buy new weapons.
DM: then you'll want to the storekeeper his name is aust