literally the story of google itself... built technology on a large corpus of existing text (the internet) for pagerank and then able to leverage and monetize it via search and ads.
But Google itself had and still is free. It's a service they provide to you without charge that, were it not to exist, your life would be almost immeasurably more difficult (as with any search engine). And most of the time it doesn't "take" from website owners; if anything, it generates more traffic for them.
When a model trains over Reddit, it may still provide a service that is free. But the way it's going, companies are charging money for access to those models and aren't generating traffic for the underlying training data/sites.
