What do you mean 'sucked up'? It's data on their machines already, people willingly give them the data, so Amazon can process and offer it to readers. No sucking needed, just use the data people uploaded to you already.
There's definitely a legal & contractual difference between (1) storing the books on your servers in order to provide them to end users who have purchased licenses to read them and (2) using that same data for training a model that might be used to create books that compete with the originals. I'm pretty sure that's why GP means by "sucking up."
This is analogous the difference between Gmail using search within your mail content to find messages that you are looking for vs Gmail providing ads inside Gmail based on the content of your email (which they don't do).
There's definitely a legal & contractual difference between (1) storing the books on your servers in order to provide them to end users who have purchased licenses to read them and (2) using that same data for training a model that might be used to create books that compete with the originals. I'm pretty sure that's why GP means by "sucking up."
This is analogous the difference between Gmail using search within your mail content to find messages that you are looking for vs Gmail providing ads inside Gmail based on the content of your email (which they don't do).