I would think certain free agent contracts would still have some inherent trade value. Let's say in a purely hypothetical scenario that the Yankees decided they didn't want to pay Geritt Cole $300 million anymore, are you saying that the Yankees would receive no offers because has has no trade value? Before you scoff at the notion, recall the the Yankees traded for Giancarlo Stanton and his $325 million contract (not a free agent contract but he got paid like a free agent). Sure they didn't give up a package with huge value, but they gave up actual assets to trade for him. The Astros traded for Zack Greinke, and included some actual valuable prospects in doing so. They received some cash to help to make the trade more equitable for both sides of course, but this is a great example that illustrates that players with big free agents are still valuable.