Amazon has been in the news lately for its tough negotiation tactics, refusing to accept presale orders for certain books from the publisher Hachette as well as some new DVDs and Blu-rays from Warner Bros. as it attempts to get more favorable contract terms with both companies. This isnt out of character for Amazon. In fact, the mammoth online retailer has a history of playing rough with suppliers. Take the case of Wüsthof, the maker of fancy German knives, whose relationship with Amazon ended in broken promises and threats. Amazon was once the largest U.S. online retailer of Wüsthof knives.