Scenes from a game of Settlers (2 of 2)

Last Saturday's Settlers of Catan was between four physicists, an astronomer, and a classical musician. MF is the astronomer, WF is one of the physicists; YHN is "your humble narrator":

MF: There should be a computer program to tell us the prices of the commodities.
YHN: But the value of each is subjective; why would you trust a computer program to value them for you?
MF: It's just supply and demand!
YHN: So you're going to assume the players are rational and devise a utility function for Settlers?
WF: By that point, you might as well let the computer play for you.

"It's supply and demand" is a slogan, not an answer. Should I take it as a good sign, though, that economics has injected something of that sort into the popular consciousness?