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The Pre costing Apple money argument is a red herring. iTunes is a freely distributed, Mac/PC-based program and doesn't require a portable media player at all. I use it purely to listen to podcasts on my PC. By your argument, I'm costing Apple money. That's true, in a sense, but it's a cost Apple has implicitly agreed to foot by providing me with free access to their product.
Putting the shoe on the other foot regarding the Vendor Id field, the USB standard is about interoperability. If Apple has used the Vendor Id field to limit the interoperability of their software, they are abusing the spirit and the letter of the USB license just as much as Palm is.
In this battle, there is no morally or ethically superior position. Either Palm or Apple could have taken the high road, but neither chose to do so.