Adrienne Mayor is a researcher who has published a lot on "folk science", the intersection between science and folklore - specifically how some pre-scientific cultures have interpreted fossils. Two interesting books she has written are The First Fossil Hunters: Paleontology in Greek and Roman Times and Fossil Legends of the First Americans.
Imagine you lived a few thousand years ago farming in what's now China and found something similar to the following fossils:
This is a picture of me about 10 years ago next to some mastodon bones found in Hyde Park, NY.
What might you think if you found a giant femur (thigh bone) like this thousands of years ago? Would it be unreasonable to think it belonged to a giant?
Interesting to speculate about, probably impossible to show conclusively.