This is just a big observation of what humans do. To be clear, what is not in contention: does obeying a society's established norms help one survive/thrive. The question we're looking for is: Does the moral language humans employ ("Humans should not murder") refer to objective moral facts (Moral Realism) or is the moral language humans employ just an expression of invented whims that humans use for surviving/thriving/comfort.
In the same way that we cannot validly reason "(1) Humans happen to practice violence therefore (2) humans should practice violence" we cannot validly reason "(1) Humans happen to practice nonviolence therefore (2) humans should practice nonviolence" (as seemingly benevolent and attractive as that reasoning may be).
The obvious comparison here is to divine retribution. You can borrow a turn of phrase from the Declaration of Independence and say that the punishment comes from Nature/Nature's God. It is encoded in physics itself. If you take the form of moral realism where morality exists in the mind of a god (though not quite the God of Christianity and absent an afterlife affected by your earthly decisions) the parallel seems clear to me.
Inside Moral Nonrealism the invented opinions can be followed or ignored and doing either will (obviously) have consequences. But this is only Hypothetical Morality -- everything is contingent on what outcome one prefers. Even with the researchers' observation that certain codes lead to societal success, we would not be able to say those codes should be followed without first declaring 'whatever leads to societal success is what we should do' which as Hume shows, however attractive and easy, remains only an assumed human opinion.
And indeed, as far as your observation of it being a fundamental structure and encoded in physics itself, Christians term this 'clear parallel' natural revelation and cite it as evidence for God.
What can't be justified from nature is the many arbitrary rules religionists came up with, like treating cows as holy, not eating pork or shellfish, wearing tassels on your clothing or funny hats, etc. etc.
Not necessary. There is an alternative route through game theory and the notion of an evolutionarily stable strategy. See, e.g., http://www.saet.uiowa.edu/papers/2015/alger%20weibull%20npla.... Put concisely, the argument is that morality is adaptive. In that way morality can be said to be real and not arbitrary.