<<Rather than making accusations having the the smell of tar and feathering, they being based on assumptions of which the accusers are certain of but which may be false,>>
I just want to add that I've gotten free self-published books (offered free by the author) from Amazon that have this same problem, with book titles/page numbers inserted within the text. This happens when self-published authors don't know what they are doing in formatting their eBooks and don't even bother to check their book after it is published on Amazon. So it isn't just PDFs or old out of copyright scanned books where this happens. And it certainly doesn't automatically mean that anyone is doing anything illegal. I've never downloaded an illegal book in my life and I've seen it several times.
<<AFAIk there is no legal way to acquire an e-book version of even an out-of-print copy unless you actually own it & scan it yourself>>
I think you are confusing 'out-of-print' with 'out-of-copyright'. What you said is not my understanding at all and I've done quite a bit of reading on this subject - only because I like to do the right thing, not because I'm trying to get around the law.