What is amazing to me, is how uncomfortable some hyper-performance cars are.
Take the Ferrari-my (very rich) neighbor has a mid-engine Ferrari. True, the thing goes like stink, and holds the road like a leech-but you are sitting on thinly-padded fixed-position seats which start to hurt after 30 minutes. plus you have that massive V-12 engine rumbling away next to you.
Quite frankly, the car is less comfortable that an old VW beetle-and the operating cost (according to my neighbor) is about $1.50/mile!
FWIW, from http://wikicars.org/en/Bugatti_Veyron:
And, from http://www.ferrari.com/English/about_ferrari/Corporate/Pages/100726_cor_CDA_Ferrari.aspx:
I was going to make a similar point about the Corvette ZR-1, GT-R, etc. I don’t know if this is true about any of those particular cars, but the major automakers have had plenty of “halo” projects where it doesn’t really matter if they’re selling them at a loss since they sell so few of them and the loss is tiny relative to the size of the company. The point of the exercise is to get people excited about the brand and other models, get people in the showrooms and maybe do a little R&D.
So part of why Ferraris and Lamborghinis have to be so expensive is that supercars are all they make, so every car (more or less) has to pay for itself.
You can slap on a supercharger to a number of engines without any modifications. That doesn’t make it a super car. However, no one has yet to define what a super car is, but the Vette is oft regarded as being able to hang with super cars, and/or beat super cars at their super car game, for much much less than super car $$$.
Carbon fiber composite is still pretty expensive (although less expensive than aramid fiber). Even though the cost of the materials has gone down, the largest part of the cost is the processing, which for all but the most simple forms requires some degree of hand layup. Carbon fiber is well suited to things like tennis racquets and golf club shafts that benefit from light weight and high stiffness, but its use in automotive applications is questionable except as a marquee signature.
As has already been pointed out, the supercars of yesteryear are all but matched by high performance production cars today. I have a mass market sedan with a few minor enhancements that will keep up with a 'Eightes-vintage 911 Turbo and will actually outrun and outhandle a Ferrari Dino/GTS (which admittedly was at the low end of Ferrari’s lineup). I recently drove a Mustang GT with about US$ 10K of enhancements at a closed high performance racing course that would keep pace with anything short of a Bugetti Veyron or Aston Martin DBS.
You could significantly reduce the cost of most supercars by employing modern line assembly methods and making slight compromises in materials which would offer the same performance and arguably higher build quality. However, the truth of the matter is that, aside from diluting the marquee shine of a limited production car, there is isn’t a great public demand for supercars. Many people like to look at them with envy, but most supercars are not even remotely practical. More practical supercar-like cars, like the Audi S8 or the Porsche Panamera are basically high build quality mass production cars that demand a premium (but still less than supercar prices) on the nameplate and extensive safety and performance features.
Stranger
It seems the main demand for supercars are the writers for car magazines. They seem to devote 1/2 of each issue to these cars that very few readers can afford. I guess it’s just like reading Playboy, you are not getting that car or that girl. 
Just 2 different types of porn.
Nope, I opened this thread to comment that historically speaking, New England hasn’t supported much of an automotive industry.
I was thinking about taking this thread and making a few global subs to see how it would read
s/car/computer/
s/engine/CPU/
s/top speed/GHz/
s/carbon fiber/double graphics cards/
etc. I’m thinking the same arguments and facts would still hold.