BC,
Almost every part of the country has a different kind of pest. Here in Oklahoma, a squirrel, is considered to be quite a tasty meal, but if you tell that to a guy from New York City, he will likely throw up:barf:
They are a real pest in the city. Other parts of the country consider Armadillos to be a pest , but in Texas, they have BBQ cook offs for them.
Wild Hogs, are a big pest here in Oklahoma, even though they are great hunting and eat very well.
Even the Whitetail deer, become a pest if the population goes unchecked.
California has laws that protect certain species, even though those species are a danger to human life, case in point, the Mountain Lion.
Your up bringing was right, and you shouldn't kill just anything that comes by, but take into account, that left unchecked, these pests will be in your yard, your cities, your house, and probably in your bed, before long.