Got lots of rabbits in my town, on a tiny nature reserve beside a footpath that goes from some office complexes to an industrial estate. It's ten minutes walk from the houses where people keep cats. I guess all those fluffy neutered cats have dedicated their attention to actual cat food and to the sport of infringing on the territories of other cats, and just aren't very rabbit-centric. If the cats were feral and breeding the rabbits might be in trouble.