I've experienced this. Actually when I received the book from Amazon I thought it was a counterfeit copy, only to discover that on the very last page it says: "Printed by Amazon Logistica Italia S.r.l". Amazon's business shouldn't be printing books and obviously they should state clearly that the book you are purchasing is printed by them. The current solution? Just return the item.
Why? There is an argument that they should make it clear a book is printed on demand but I can't see why they shouldn't be in the business of POD.