We humans don't have a particularly good record when it comes to rational thought and the land. While I regard cats as a major pest species with terrible effects on wildlife I am no sadist. I dislike having to kill anything, but do so on occasion.
I admire wild cats in their native habitats, where they run the risk of being devoured by other larger carnivores and live amongst prey animals that have evolved to handle them, so are seldom annihilated. Australia is no such place. our native predators, such as quolls, were bloodthirsty enough and efficient predators, but no match for cats and foxes. Every 10 years or so in a 150 kilometre radius from here, someone reports a spotted-tailed quoll. Maybe they will hang on, but their prospects are not great.
You can pretend to have ethics about wildlife and cruelty, but as you live you cannot help your footprints crushing some life out of the ground. Yes people introduced cats. Should they be punished? Lobby to get our laws changed and find resources to police them. Poor cats. No it is not their fault. Nor is it the fault of hundreds of bird species, little lizards, baby snakes, tortoises, marsupial mice, possums and even young wallabies that cats play with them then kill them, often not even for food. Poor cats, if only they were human we could re-condition them to make them socially and ecologically acceptable. But they're not. We haven't even managed that for humans. They do a great deal of harm to our remaining wildlife (both cats and humans).
So, should we ignore this problem? I can't take on a cat crusade. Maybe you can. But I can try to deal with the problem as I can, when and where I can, with the limited resources available to me. But it is hard. Especially when the sole condition for land ownership and management is bank credit. As a result people from urban blocks move onto 10 hectares thinking they have boundless freedom for their pets. Around me even now I have neighbours that release their cats onto their farms and into the bush, refusing to desex them (too much bother and expense). Their kittens get disease, killed by other predators (including other cats) and the toughest survive to prey on the wildlife that even in this relatively remote rural/bushland area is in decline.
What are our options? Prevention is best, but the cat lobby is fierce enough to ensure the active disinterest of any government, Federal, State and especially Local. Educating my neighbours is an option but their perceived emotional needs to play with purring kittens outweighs my most diplomatic efforts. Most of my neighbours, fortunately, don't keep cats but the two who do feel no guilt in their pets' unrestrained access to our land and wildlife.
How vegetarianism got into this argument is beyond me but, if you've ever really surveyed land managed by people check the wildlife. Clearly natural bushland contains a greater diversity of native species (depending on many factors). Grazed country where tree and shrub cover is maintained with patches of native vegetation remaining is also reasonably rich in native animals. But commercial crops are generally managed in a far less wildlife friendly manner, using a range of chemicals and bird deterrents. Of course larger mammals are often out of the question in such areas. Apart from the farmer with his shotgun aiming at cockatiels, I hope you are prepared to spend time and energy trying to convince the many gun owners around that killing ducks, quail, kangaroos (etc.) for fun or because they are perceived to be vermin is really not a good idea. Then deal with the city blokes who visit their country mates and shoot willie wagtails because the kangaroos were smarter than them.
In this forum I have (apparently falsely on occasion) supposed that the major interest of participants is the observation and conservation of native birdlife. Cats are a problem that needs recognition in a level-headed way, with appropriate responses and management. No effective lobby exists currently to address this issue. Too frequently our emotions eclipse our ability to reason (happens to me all the time). In the meantime, if I am able to do something to help reduce cat densities as part of a far greater number of other techniques to manage my land for the benefit of native birds, I will. And yes, I am sorry for any discomfort caused to cats, but I just am more sorry for the discomfort they cause our unique natural ecosystems.
Greetings from the northern Southern Tablelands of NSW