They can be set on fire with a Torch or Lighter to produce sparkles, and will be destroyed in the process. When set off, nearby Mobs such as Hounds will be startled and cower in fear, giving the Firecrackers a use apart from the festivities.
Red Firecrackers are also introduced in the Hamlet DLC. During the Pig Fiesta, Pigg and Pigglet's General Store will sell Firecrackers during the event for 1 Oinc each and Pigs will occasionally dance and throw Red Firecrackers on the ground. Firecrackers appear 4 times as often in the shop.
In the Hamlet DLC, the game will freeze when a Firecracker exploded inside a container.