Hmmm. . .makes sense, but I'll have to think about that. Assuming they had domesticated cattle, it would seem the first thing they would do is eat some of the cattle as well as some of the plants the cattle ate.
Yes, cattle are food, but a society that can milk cattle is stronger than a society that is dependent only on their meat, as it has a more stable food source. Stone age societies couldn't slaughter cattle every day.