Why are Selmer Mark VI Alto, Tenors and Soprano saxophones so expensive?

Selmer is a very old instrument maker have a lot of prestige among musicians. Just like expensive cars its half quality, half the name. In my opinion they are indeed great horns because they used a finer quality of bronze in the alloy that creates the instrument. As the saying goes "they don't make them like they used to." Is very true for any brass instrument. However paying over $20,000 for one is kinda outrageous unless it is completely flawless and decked out and ready to play with a premium mouthpiece.