Some animals like snakes simply swallow prey whole. Dogs and pigs are known for eating hastily with minimal chewing, and I'd imagine many other predators are the same. No idea how efficiently their respective digestive systems extract nutrients from solid mammal chunks.

> Dogs and pigs are known for eating hastily with minimal chewing,

Because they have no or smaller cheeks. But they have very acid stomachs.

The Comparative Anatomy of Eating

http://www.vegsource.com/news/2009/11/the-comparative-anatom...

Omnivore or Herbivore?

https://livinontheveg.com/omnivore-or-herbivore/

Milton Mills, MD: Are Humans Designed to Eat Meat?

https://www.youtube.com/watch?v=sXj76A9hI-o&t=66

I was under the impression that it had more to do with lips than jaws. Hyenas can outbite humans a thousand times over, but they can't drink a milkshake through a straw!

In other words, breaking bones is the easy part; sucking out the marrow is the tricky bit.

One of the reasons why dogs gnaw on bones is to get at the marrow inside.

Hyenas are known to eat bone. The bearded vulture is the only known bird that eats bone marrow, and cracks open bones by dropping them on rocks from a great height.

The article talks about primates but there are similar theories about other brain-and-marrow gastronomes.

https://blogs.scientificamerican.com/laelaps/inside-the-brai...

I'm imagining that the humans might have taken the bones somewhere else to deal with them, possibly breaking them open with stones.