I think daycare is different than parenting in that your job as a parent is raising a productive, compassionate, and loving human, while a daycare provider's mandate is "dont let them die before 5 pm." Both are important jobs!

Depending on the pets, sometimes two can be less work than one. They entertain each other and play together, resulting in less destruction and less demand for attention from their owner. That probably all goes out the window with more than two though!