It is sad, I agree, that people would want to buy such an item. But it's just a book and as such I don't see how it could reasonably be banned from sale, however much you dislike the motives of the purchasers.

What's worse is that people who commit crimes or fraud or whatever, usually end up making a huge profit from whatever they've done wrong, by selling their story to the press, or writing their memoirs, etc.

And people buy them by the shedload.

I'm not sure what can be done about it, unless you have a law that forbids criminals from profiting directly or indirectly from their crimes. I'd like to see such a law in place.