I too quite like cats, don't have one nor want one, but those who have 'em as pets, they must keep them properly corralled in order they can't get out and wreck the environment. We've two 'bow wows', a Kelpie and a Labby, and the same goes for them, keep them well controlled behind a sturdy fence and just enjoy them, without letting them roam around and uncontrolled, thus buggering it up for everybody else.

Yes I must admit one of my favourite responses to the question, "do you like cats" is, yes I luv em, but I've still got one in the freezer.

But seriously, addressing the cats is only treating the symptom, the cause is irresponsible owners and the way to fix that is a two step approach.
1. Mandatory de sexing and registration (unless you are a registered breeder)
2. Fines for allowing a cat to roam freely in public spaces.

Breeders should also be fined if they sell/give away an entire cat to an owner that is not a registered breeder.