Even for authors seeking rent, I imagine that having their work in the LLMs' knowledge base is worth much more than the pennies they could charge for using it as training data.

For example, I recently asked ChatGPT to summarize book 1 of the Wheel of Time series because I had read it a long time ago but forgot most of it. Getting the summary and being able to ask a bunch of questions to bring myself up to speed made me more excited to read book 2.