If you have ever made a painting and sold it, then you too profited from the work of thousands of artists. How so? Because your sense of what is art came from those who preceded you. You have seen the works of Picasso, Rembrandt, Monet and so on and your brain absorbed from their work, just like an LLM.

If an LLM generalizes from thousands of authors then it is no different from what your brain does.