The hunters said 'a tree might fall on you and kill you'? This is supposed to be a nugget of ancient wisdom. Now it turns out it's actually a coconut falling out of the tree? Are you providing this extra information? Or was it somehow implicit in the original telling?
Is it possible that both the original teller, the reteller and you too, are starting from the (unfounded) assumption that the hunters know what they're talking about, and are adapting the facts to fit this assumption?
I read somewhere that the Mongolians believed flowing water was sacred and they had a taboo about defecating near it. For the wrong reasons they accidentally prevented cholera. If avoiding sleeping under trees prevents tree falls, lightning strikes, coconut comas, snakes from dropping on you, and whatever else then it doesn't really matter why the hunters don't sleep under them does it? Not having coconuts to worry about is just a happy bonus to the survival statistics.
Is it possible that both the original teller, the reteller and you too, are starting from the (unfounded) assumption that the hunters know what they're talking about, and are adapting the facts to fit this assumption?