I don't want to rain on anyone's parade, but I recently heard a statistic claiming that the average pet dog eats more protein in a week than the average sub-Saharan African person. Makes you think again doesn't it.
Cats don't get off lightly either; they are a menace to wildlife. A friends moggy killed an endangered water vole a while ago.
I'm not saying don't keep pets, just that having a huge pack of enormous dogs or loads of cats is possibly not the most responsible move.
Just for the record, I like cats better.
Mutate and Survive