I've heard this said about cats, that cats view humans strictly as food dispensers. But I've personally seen cats develop separation anxiety when they thought their humans weren't around -- and then settle right down as soon as a familiar human come into view. To a cat, humans provide some manner of physical and emotional security as well, to say nothing of affection.
It's the same with any healthy human relationship. Can you imagine how sad it would be to make extraordinary efforts for a person who did absolutely nothing for you? We reward those who provide us something of value -- security, affection, a sympathetic ear -- with our sacrifices.
I've had a cat eat my hair which is a grooming behavior they otherwise only do with other cats that they trust. If that isn't evidence of some kind of mutual relationship then I don't know what is.
Imagine going through the effort to domesticate and entire species to provide fire, food, shelter, etc. and then have them wander off somewhere without asking. At least they still upload those funny worship videos to the internet.
Cats are also very aware of changes on their habitat and are kept in way too small space to express natural behaviour. Most house cats are extremely stressed. You can see this if you even move one bigger object in the house and watch how the cat gets anxious. The behaviour is much more complex than the human emotions we project to cats. They are different, we don't know how they feel. But most cats are not "happy", we just fail to see it and laugh when they run around and do stupid things out of boredom and stress.
Edit: Also Stockholm syndrome... And would cats hang around humans if living in their natural habitat and not receiving food from humans? I don't know.. But the spectrum of "do they care about humans or not" is much wider than just that question.
Domestic cats natural habitat is not a 40sqm flat without the possibility to go outdoors. Also, domestic cats were not bred by humans for domestic characteristics but to keep places clean of animals such as mice. Anyways, that's beside the point: cats reality is complete different to ours and trying to describe cats behaviour using human characteristics is a poor way to describe their behaviour. Even as mammals, they still have very different senses and perspective to everything. We have very limited understanding about their "feelings".
It's the same with any healthy human relationship. Can you imagine how sad it would be to make extraordinary efforts for a person who did absolutely nothing for you? We reward those who provide us something of value -- security, affection, a sympathetic ear -- with our sacrifices.