How do we know if they eat grass to throw up or do eat grass and then throw up? It is the what came first, the chickenor the egg?! I allow Mabel to eat grass because she likes to. she likes to pull it up and will munch like a goat! She throws up maybe 40% of the time! She also loves to dig holes and root around in the GA red clay! We really can't tell what color she is because she is permanently stained! The vet commented that she was not very delicate or refined! She is terrier 110%!!!