Everyone who deals with vendors has a choice to make. Should you beat them up and show them "who's boss" or should you partner with them in the spirit of cooperation? Which one do you choose? Can you do both?
There are a lot of articles on managing vendor relationships, many people much smarter than i am write articles and books on this topic. However, there is a fundamental, philosophical choice that i see companies (and individuals alone) make when dealing with vendors. Are they open and honest and treat their vendors as partners in advancing items at their location? Or do they constantly demand more and more of the vendor and want to pay less?