I'm from a Jewish family that has been unable to pass down its rituals over the past few generations. My great-grandparents were observant on both sides. I have no religion or inherited rituals to speak of. So how does a ritual get successfully passed down for something like 500 generations? What must the observer get from it that motivated them so strongly to pass it along with the necessary vigor? Was it something…
I think small, pre-literate societies on the edge of survival rely heavily on "traditional" knowledge, and for very good reasons.
One of my anthropology professors told me a story about a village (I forget his source for this, but it sounded like he had one). They had an old woman, probably in her 80s, toothless, partly blind, and mostly immobile. She only survived because of a significant ongoing effort of the village.
Then the village had a bad year, a famine. And the old woman said, "This happened when I was a child. What you need to do is take the leaves of such-and-such a plant. They're poisonous. But if you beat them with rocks, soak them, and let them age a bit, then they're disgusting but edible." And so the village remained fed. The old woman was contributing to the village's survival, because she was a source of mostly-forgotten knowledge.
Similarly, we know that modern hunter-gatherers might be able to find and identify 47 species of edible mushrooms in their local climate. This knowledge base can easily be the equivalent of a college education focused just on finding food.
Now, inland Australia is famously one of the most inhospitable places in earth. Early European explorers noticed just how difficult it was to survive there. But the locals someone managed just fine. They knew all the tricks.
So my guess is that the kind of society which can remember how to find and prepare 47 kinds of edible mushrooms, or which can survive a famine that occurs every 75 years, or which can survive inland Australia, is a society with significant respect for ancestral knowledge. Learning the rituals may often be a matter of life and death.
The modern world is different because we have books, and science, and high division of labor. If we forget how to do our grandparents' jobs, someone else will still learn. Or the nature of work will change so much that a new generation needs to learn a new way of working.