The A's never do this, that's why they're almost always in the race to the end. Do you think A's fans were happy losing Mulder or Hudson?.., No, but it's what allowed them to keep Chavez and Zito. A small market team has to pick their battles carefully and know not to get into a bidding war for their vets that they can't win.
But the A's traded these guys nearer the end of their deals, AND got more back than you're offering. And neither were as valuable as Bay. It would take at least one of your absolute stud prospects (Wood or Jered) plus a couple of good ones to get Bay.