Well, there are people out there that have found themselves in the position of having the ability to have anything that they want. Maybe they wear them, or maybe they just like to hold them on occasion and look at them. Like the article says, even at these nose bleed price levels, the manufacturers don't actually make that much off of them due to the cost of resources they put in them. Thus, they really only make these for the "halo effect" that they generate for the rest of the manufacturer's products.
Even though I'll never be in the position of buying one of these, I'm happy they exist as they do provide the ability for manufacturers to show their prowess in innovation and design. Plus, I feel that eventually "trickle down" will happen. Thus, the people that buy these $700,000 monsters are actually financing the development of cool features in the more standard offerings. After all, once you've proven you can do something, making clones of the bits that comprise the complication is much less expensive.