WMG / Zip Zip

The Livingstones secretly know that their pets are wild animals

Even if their Paper Thin Disguises were enough to fool passers-by at first glance, the people they live with and care for them would have to find out eventually. Being the animal lovers they are, perhaps the Livingstones were actually willing to take in a fox, bird and a couple of boars but decided to simply play along with their ruse so as not to cause suspicion or alarm to the rest of the neighborhood.