Hello! It is perfectly normal and necessary that buns eat their poops, which are a special kind of poop called cecal poops. They are partly digested foods that then get re-digested so that the bunny gets the most nutrition possible from it. Bunnies eat low nutrient high fibre foods like grasses, hay etc, which they need to eat a lot of to get the available goodness and the amount of fibre necessary to keep their gut working well. Here is some info for you!
From
https://www.sandiegorabbits.org/health.php
THE SCOOP ON POOP
Cecal pellets (aka cecotropes) are a special food made by bunny, just for bunny. They are partially digested foods that are passed from the bunny and then reingested. You may not see bunny do this, but when she appears to be bathing her belly and she comes up chewing, she's probably just taken up a cecal pellet. It is from these cecal pellets that a rabbit gets the majority of her nutrition, not from the first passage of food through the gut.
Unlike most other mammals, rabbits produce two types of droppings, fecal pellets (the round, dry ones you usually see in the litterbox) and cecotropes. The latter are produced in a portion of the rabbit's digestive tract called the cecum. The cecum contains a wild brew of bacteria and fungi that are normal and beneficial for the rabbit. In fact, the rabbit cannot live without them, since the cecal flora produces essential nutrients (e.g., fatty acids and vitamins) that the rabbit cannot produce on her own.
How does the rabbit get those vitamins? She eats the cecotropes as they exit the anus. Sound disgusting? Not for a rabbit. When she's enjoying her favorite, home-made snack, she'll tell you how delightful it is with that blissful, soft-eyed face and butt-twitch that signals all is well with the world.
Cecotropes are not feces. They are nutrient-packed dietary items essential to your rabbit's good health. A rabbit usually produces cecotropes at a characteristic time of the day, which may vary from rabbit to rabbit. Some produce cecotropes in the late morning, some in the late afternoon, and some at night. In any case, they usually do this when you're not watching, which might be why some people refer to cecotropes as "night droppings."
Normal Intestinal Products
Anyone who lives with a bunny has seen a FECAL PELLET. These are the small, brown "cocoa puffs" that we all hope end up mostly in the litterbox. They are round, relatively dry and friable, and composed mostly of undigested fiber. Rabbits do not ordinarily re-ingest fecal pellets, though a few bunnies seem to enjoy an occasional fecal pellet hors d'ouevre. A normal CECOTROPE resembles a dark brown mulberry, or tightly bunched grapes. It is composed of small, soft, shiny pellets, each coated with a layer of rubbery mucus, and pressed into an elongate mass. The cecotrope has a rather pungent odor, as it contains a large mass of beneficial cecal bacteria. When the bunny ingests the cecotrope, the mucus coat protects the bacteria as they pass through the stomach, then re-establish in the cecum.
