Peppa literally has a pet goldfish. There's a vet who takes care of a tortoise. There are ducks in a significant amount of the episodes, and they act like normal ducks. They don't walk on four legs. They don't talk. The weird one is Peppa.
I imagine it almost as a prison where they drug there worst people of their society to a point where they revert to there old ways of being a untame creature to create a full perfect nation of the best citizens without flaws