Here's why:
* They don't have venom: Daddy long legs are not spiders and they don't have venom glands. They can't inject anything into their prey.
* They don't bite: They don't have strong enough mouthparts to bite a chinchilla.
* Their diet: They eat insects and other small invertebrates. Chinchillas are much too large to be considered prey.
However, a chinchilla might be startled or distressed if a daddy long legs gets too close, leading to possible injury from jumping or running.
It's best to avoid introducing daddy long legs to your chinchilla's environment, and to keep their living space clean and tidy to discourage any insects from entering.