If someone put it in there, it doesnt actually matter what it really is, just what it looked like to them. If it quacks like a duck, swims like a duck, and tastes good in an hoi sin sauce, it may as well be duck.

So if you come from a culture that revers something in a certain way, and you find something that is like it, you place it in a reverential setting. By your own customs.

If a celt found it buried, and celts practiced shaft burials and sacrifices, they might connect it to those practices and see it as sacred. Never mind if it is wood, they think it's wood, turned to stone by the gods, maybe. So yeah, they can see its old, so place it in the oldest known place of the ancestors you can think of, give it back, so to speak.

The upturned tree at Seahenge, by the way. Surely the first time Time Team didn't leap on a lurid "sacrifice" theme, but did it come up it might have been a shaft burial? Was it ruled out? That would have made it a place with remains underneath, and would have different rules governing it maybe??