This happened when I was a zookeeper...

We used rubber buckets a lot for carrying things like food for the animals and pretty much anything else we needed to carry. So the public was pretty used to seeing keepers feeding the animals from buckets.

One day, I was filling a drainage hole in the Collared Peccary (outdoor) enclosure with some rocks, which I carried in my bucket. There was a woman and a child standing at the railing, looking into the enclosure as I approached. As I was entering the enclosure, the woman said to the child, "Look, Jason, she's going to feed the animals." The child watched me as I poured the rocks from the bucket into the hole, and said, "Do they eat rocks?"