Nicely put. Now explain that to someone who only has interest in what facilitates the lifestyle they want to live. It's our willingness to put the value of a financial transaction above other recognized values, like helping someone, improving the quality of other's lives, and things that are less tangible than cold, hard potential. Ask most people any question about how much it will take them to do something, and they can give an answer. They may not want to, but they can. The problem isn't with the medium of exchange, it's with human attitudes. Under the barter system, people could still be cheap, greedy misers. Greed isn't a new phenomena and neither is an economic system where it can run amok and reduce the quality of everyone's life. So when people talk about needing a new core economic system, I think it's just trading one way people hoard for another.
If we're so evolved, then we need to start focusing on the real problem, which is human attitudes about wealth, sharing, cooperation, altruism and greed. That's an even less tangible goal than an economic system that can't be anything but fair (if that's even possible), but I think these sort of social/spiritual things are what we're not giving any mind to these days and we're seeing the direct results of it. If we raise a generation that doesn't dream about being rich, maybe we can have a world where there are things where everyone won't put a price on. I know that's all very mushy, but I think it's going to be important the more tightly knit the world becomes.