And this was actually a significant controversy some years back.
A lot of users, including myself - though definitely still a small minority - quit Reddit over the increasingly aggressive monetisation attempts; some of us used automated history editors to prevent our posts from being scraped or searched (though it almost certainly will not remove them from back end databases).
We didn't know that this was the specific way our content was going to be used, but we knew it was probably going to be something we wouldn't like.
We have now been proved right, and if you decided, back then, to stay and keep contributing to the multi-billion-dollar site for free, now you know why the Cassandras were raising such a fuss.