If iPods follow in the steps of most other retro-tech, prices will get silly and then people will come along that have been sitting on warehouse liquidation lots of new-in-box units that have been sitting in a corner somewhere for 40+ years. Someone (more likely several people) is sitting on boxes of these things that were unsold at some electronics store or promotional outlet when the new model came out and they were removed from the shelves. Not to mention individuals who bought units and never opened them (ex: underappreciated gift, spare that was never used, duplicate gift, already owned one and won another in a raffle...) for whatever reason.
Odds are it is way to early, and these were produced in way to high of numbers, for ridiculous prices like this to be justified by actual number of like condition units out there. This is not like an Apple I where it was a limited run of hand-built units, this was a major mass-produced device with around 400,000,000 units in the wild. There are likely plenty more units exactly like this one out there.