For those who don't know, here is a brief summary of the Animal Crossing series: you play as a human who is moving into a town inhabited entirely by animals. You take care of the town, fish and catch bugs to earn Bells (the in-game currency,) and more.
Isn't it strange that you're the only human living in the whole town? The only other humans you interact with are your mother, who will sometimes send messages to you, and other players online. Well, what if the reason you're in a town with no other humans, only animals, is because of segregation between the two species?
Think about it. One of the messages your mother can send you mentions how she doesn't understand why you'd choose to move to a town inhabited by animals, as if they aren't normal members of society. The animals are also very kind and almost subservient to you, as they will often ask for your advice and will get very sad if you leave for a long time, like they depend on you. My theory is that humans are seen as above the animals, and the animals are seen as lesser compared to them.
However, the animals are very polite when you move in, and greet you as if you're one of them, (though sometimes they'll mention how you have no tail or feathers or fur.) Maybe they've been raised to respect the humans, and are too afraid to say anything that may upset them and start an altercation.
I don't know. It's a dumb theory, and it doesn't make sense why you'd chose to move into a town with a lesser species, but I wanted to get it out there anyway. So yeah. Thanks for reading this theory of mine