This is the 'problem' with cats that a lot of people don't/won't understand. Yes they are (partially) domestic but it completely depends on the personality of the cat. You can try all you want to train it but some want to be outdoors most of the time.
I had 3 at one point. One used to roam when younger and hunt. As she's got older she doesn't leave the garden (can no longer jump the fence) so uses my garden but often comes indoors to use the litter tray (i HATE the word sh!tbox). My middle cat (who died last year) never roamed and would come inside to use the litter tray. The youngest cat also won't leave the garden as she's petrified so also uses a litter tray.
Our neighbours cats are often in my garden. Everytime this happens, my youngest cat gets scared and pees on something, usually an item of my clothing. The cats are in my garden most days so you can imagine how many things get peed on. I don't get angry at the neighbours cats (wish mine would tell me what the issue is!), they are being cats. I don't get angry with the neighbours either.
Cat's aren't dogs. You can't train them like dogs. The comparison just doesn't work.
When I say domestic I think the point I mean is if the owner didn't buy and introduce the cat, it wouldn't be there. I know they're nowhere near as domesticated as dogs in the trainability sense though.
Me and my neighbours don't clash at all about their cat, they know I use the chilli powder and are ok with it. The other week they spotted 'a mahoosive dead rat' (in their own words) in my front garden that was left by their cat and picked it up before I got home. I know for a fact that if I asked them to clean their cats poo from my lawn they would, but they're so nice I'd never do that.
I got offended earlier because people were making me out to be someone who hates animals and is cruel to them, which I'm not at all. As you can see above me and my neighbours have found ways to deal with it between us, and I like their cat too.