> The main question is why aren't they leaking it to AA themselves?

How is this a question at all? They’re scanning books because the courts determined that it’s the only way to use that data. They are forbidden from using digital copies found on places like Anna’s Archive. They must acquire and scan the book.

They cannot redistribute the book. The Internet Archive tried that and the courts shut it down. You cannot scan a book and share it without violating copyright law.

> You cannot scan a book and share it without violating copyright law.

Hence the “leaking” part.