Alex, there may have been some misunderstanding:- I did not say cats do any real harm to humans, but they do indeed do real harm to native animals & birds in my region - by real harm, I mean they kill them and from what I have observed they are not even doing it for survival (food) purposes as they usually dont even eat their prey.
So if they want to kill something for fun, I would much prefer they killed mice, or preferably mosquito's.

'you sound like you expect animals to behave in a certain way because we humans decided so'
It is my understanding that humans introduced cats to Australia, so perhaps its not unreasonable to expect humans to take some responsibility for trying to control the native animal & bird killing habits of cats in our region?

Obviously you are a cat lover, whereas I try to love all creatures equally (except for the odd mosquito, spider or snake:)