Items placed under large snowballs, including other large snowballs, cannot be picked up.
Large snowballs melt slower than regular snowballs, and will not melt if stored in the inventory.
Vault inventory classifies these as "Other Items."
Large snowballs are most frequently used as a building material due to their convenient shape, not to mention the fact that they are easy to obtain. Players can build snowmen and other structures with them, however the most frequent use of large snowballs is to block the town entrance.