what is the desirability of this pipe to make it sell for so much?
I am no expert, but IMHO I would guess it comes down to "collectability". Certainly craftsmanship and beauty of the pipe is a huge part of it, but when it comes to collectors, desire for an object they fancy often trumps common sense (no offense intended to collectors).
The same question could be asked of any collectible. A show I enjoy watching is Pawn Stars (even though I am fully aware it's not reality, but "scripted reality"). Nevertheless, time and time again you'll see things like a pair of sneakers going for $5,000 or a plastic Star Wars toy, still in package, getting $3000.
Is a piece of plastic in a cardboard box worth $3k? Of course not - but it's not about actual value, but perceived value. If enough people want it, that inflates the price.