If anyone wishes to know the full reasoning on why the zoo has a Domestic Cat here, PM me. I'm only explaining via PM, just in case the zoo does not want the reason online. They probably don't mind, but I'm just playing it safe.
You'll get no argument from me that both cats and dogs can be pest species, and I am neither a cat nor a dog person. However, in the context of a farm exhibit along with other domestic species they do make sense.
Perhaps has the zoo develops this can turn into a more conservational thing. I mean, I think the whole idea of the New England Farmyard is to show both wild and domestic species living in a common farm setting so why not one day make it into a whole "what harm cats can do" thing. They already display Brown Rats next to the cat, which is a pest in its own right.