Satyrican,
While your basic premise that supply and demand determine value is true as an economic principle, you are leaving out the assumptions economists make to reach that conclusion, namely that the attributes of the product are well known and there is plenty of liquidity.
Take your Mercedes example. They cost a lot because their value is well established in a liquid market place. People know they can resell their car for a good price and that the cars are reliable. This can not be said about the system vending industry. If normal economic rules applied to system vendors, then almost all systems should be free. I agree with FinStat that I have yet to see a commercial system be so consistently profitable that it merits an increase in value. In the VAST majority of cases, there is incompetence in the system development (i.e. curve fitting, unrealistic assumptions, etc.) at the very least, and in many cases, straight up fraud. Just take a look at the CFTC website and see how many regular advertisers in the major trading magazines have had rulings against them.
The fact is that vendors rely on "perception of value" since there is imperfect knowlege of their systems to the public, and so they base pricing on basic human greed to allow them to charge prices that are not justified by the product.
Just as acrary mentioned, if a system was truely good (assuming the idiot developer sells it instead of trading it) they would offer to sell it on the condition that a percentage of the realtime profits would be used to pay for it. That is the only fair way to do it, so why have I never seen a single system sold this way? (Hint: because there are no good ones for sale)
