The problem with comparing saxophones and flutes is that, to me at least, the flute market is innundated with gimmick and marketing myth which drives the going prices. Shoot, those aren't even the expensive flutes that you listed. Haynes' flutes can go for over $40,000 and involve years of waiting. The real thing that does qualify a flute for such a high price is the fact that in that range, they are almost completely handmade wereas saxophones these days aren't. Yet fourty years ago, saxes were mostly hand made instruments, yet they didn't garner the prices on the order that flutes do these days. You could claim that high-end flutes have very delicate mechanisms and pretty much all have soldered toneholes, adding to the complexity of manufacture, but that doesn't answer the disparity for me, to add to which, a saxophone typically has more parts to manufacture.