Unfortunately, I didn't know that, but I wanted to make some minor changes to the spines of my printed books, so I guess I had to. I've searched, but if lulu has said this somewhere, I can't find it.
The problem for lulu, as I see it, must be that a lot of people have decided to use lulu as a way of distributing material for free as downloads and don't have any intention to sell anything, something I don't think lulu intended. Perhaps lulu should change its business model to only allow authors who sell downloadable product to have free downloadable content. I have a collection of short stories and a song for free, but these are intended to be samples to attract potential buyers.
Whatever the case, I still feel that this has been badly handled by lulu.