Martin Atkins posted a Facebook note about the auction where he explains that despite putting a $20,000 price tag on it, he's not expecting to get $20,000 for the tape, it's just set up this way so they can privately review bids. They're going to be posting samples on Facebook at some point.
And now I'm going to editorialize a little bit, which maybe I shouldn't do because I'll probably come off sounding like an ass. I find it a little ironic that shortly after Trent Reznor finally got access to his first album - which in all likeliness, he'll never fully own the rights to - someone else is putting an exorbitant price tag on early music that Trent recorded and, in this case, freely gave out to people. Certainly not everyone who got copies of this tape still has it, and chances are this is one of the only remaining cassette copies out there.
I'm reminded of the way people would sell bootleg audio and video from Nine Inch Nails on eBay. Fans paid out the nose to merchants who often didn't share the profit with the original bootleggers who made the recordings, never mind the musicians who made the music. That market was happily eviscerated as the NIN fan community made a great effort to put as much of this bootleg material online for free. In many cases, this lead to bootleggers posting audio and video online themselves, and this eventually mutated into fan-organized documentary films like those found on ThisOneIsOnUs, whose quality far exceeds that of the bootlegs you used to have to shell out $30 for, and even that of many 'professional' or 'official' concert videos.
Anyway, regardless of my view on who sells what, auctions like this will continue to crop up so long as there is a market for them - and there's definitely a demand for this stuff. It's not my place to tell other people what to do with things they have in their possession, but I probably wouldn't have even added commentary to this post if the arbitrary price associated with the cassette wasn't $20,000. I hope we all get to hear what's on that tape without someone buying it for the price of a used mid-size sedan.