NPR is reconsidering its linking policy. As might have been gathered from earlier answers, it sounds like it was a fit of goofiness from Legal in response to some real problems.
We have encountered instances where companies and individuals constructed entire commercial Web “radio” sites based on links to NPR and similar audio. We have also encountered Web sites of issue advocacy groups that have positioned the audio link to an NPR story such that one cannot tell that NPR is not supporting their cause.
I understand their concerns, but I think policy can be written appropriately to avoid the latter sort of problems, and copyright infringement is the protection for the former. Heck, simply add a ten second blip to the end of each file with the appropriate copyright and disclaimer text.
Ironically, the policy page still ends with the warning that this post right here is prohibited.