Happy indeed! Watching that makes me happy too. I grew up with Hereford cattle that look just like that, and they could certainly become a bit like pets, when they've been on the same ranch since birth.
No doubt some humans can manage to make a pet of nearly any animal. I'm married to one of those. It's just astounding to see the relationships she develops with horses and cats. Hell, we even have a hawk here that may as well be a pet. I've never actually petted him, but I've fed him mice from my hand twice before.