The link between abuse and trap and kill?
It isn't as far fetched as it sounds. When I looked at the David Hooi article the first thing that came to mind was that I had just been told about a complaint by someone in the same area. According to the person who emailed, the person had just complained to the town council and she was worried about the cats there.
I do believe this email may have some basis as this is not the first complaint that we have heard of in the area and the town council has trapped the cats there in the past(including sterilised ones).
Now most people will realise there is a difference between abuse and trapping and killing. However someone comes along like David Hooi, who has been diagnosed with anti-social personality disorder. If he sees the town council trapping the cats, what is he going to think? That it's perfectly okay to take the cats away and kill them.
It does not even take someone with a personality disorder to make this leap - I have had someone ask me once why he couldn't just get rid of the cats himself. He said it would save everyone the time and money if he just took them away and got rid of them himself. It was only when I explained that abusing a cat was against the law that he said he would go through the proper channels (which might still of course involve trapping and killing). Quite a few people do make veiled threats on this matter - fortunately most do respect the law and when warned will not take matters into their own hands.
If the culture of complain and kill is often seen to be the solution though, then cats' lives are seen to be valueless. They are just pests to be gotten rid off. If we are taught that anything that is an inconvenience should be done away with, then I worry about our future as a society.