>>12327721We really need a copypasta of our collective, agreed-upon headcanon for this.
In the early threads, we established that they live in the Hollow Shades (canon city on canon map, pic related). It's a forest that has a thick canopy, and like the Everfree, it's always dark there. Naturally, the bat ponies found it a very suitable place to migrate to. They used to live in the Everfree many centuries ago, but they got tired of dealing with monsters and shit so they left.
As for the bat ponies themselves, they're nocturnal. Their eyes are really sensitive to light, so they find the day irritating--they also have better vision in darkness, and have the option of using echolocation via screeching or clicking their tongue. They also sleep upside down.
Diet is mostly up to your head canon, and seems to be the most volatile topic on bat ponies, here. Personally, I take them as having a diet like normal ponies, but have a particular fondness for fruits, especially exotic fruit like bananas, mangoes and lychee.
Other people like to pin them as vampire bats, where they feed on blood.
And a small number of people label them as insect-eaters, like regular bats. But, as an established and civil society, I don't believe they really indulge in this.