When I worked at a farm in a rural town, I met a man who told me his senile mother lived in a trailer full of dozens of cats. I was thinking, 'yeah, who's senile mother in this state DOESN'T do that, right?'
But then he casually told me how he went to her trailer one day, dug a hole in the yard and then proceeded to start shooting cats with a .22 pistol and dropping them in the hole. I didn't say another word in that conversation I don't think. Somewhat in his defense, his mothers neighbors were complaining loudly against the invasive felines as well as most of them being pretty sick with cat-type diseases, snotty eyes, etc. But still, there are other ways to rid yourself of a passel of cats.