Frostbites do not know how to use snowballs, despite snowballs being essentially less powerful ice balls. This is may occasionally be relevant to survival, as a frostbite which spawned with CanPickUpLoot:1b and no ice ball may pick up the drop from a destroyed snow block/layer or slain snow golem while pursuing the player.
While it would be reasonable to call this a feature request, the thematic inconsistency is strong enough that I felt it prudent to get Mojang’s opinion on this.
To reproduce
/summon frostbite ~ ~ ~ {equipment:{mainhand:{id:snowball}}}
Observed behavior
The frostbite does not throw snowballs at you.
Expected behavior
The frostbite would throw snowballs at you, since snowballs are just ice balls but less powerful.
Can confirm