Why does a dog eats a bone?

Question
Why does a dog eats a bone?

Answer
Why does a dog eat a glove, a pillow or a shoe?   Some dogs will eat anything.

If you want to give your dog bones, they should only be hard beef bones. Long and hard.  If your dog chews and/or eat soft bones (ham, chicken, lamb) there is a risk that the bones will splinter and cut up the stomach lining and anus as the dog passes it.