Thanks for the responses
woodburnbob
>Moses, I think you are quite right about supermarkets, which I think function much like a vending machine. On the other hand, there is a healthy tradition of bargaining found in all sorts of venues, e.g., estate and flea market sales, newspaper classifieds ($100 OBO), new and used car dealerships, and so forth.
I fully understand a portion of the public avoids dickering or bargaining and pays the advertised price. While I seldom attempt to dicker with vending machines or store clerks, I don't accept the idea of a fixed sticker price when buying a car, expensive tools, machines, real estate, or anything where the markup is widely known to be in the 30% to 100% range.
Obviously, one has to be willing to ask to speak with someone with the authority to negotiate a price. My experience is that at new car dealerships you won't be speaking to that person until you've sequentially frustrated and burned out 3 levels of functionaries. I think of this as dickering by attrition.
Ian, thanks for the analysis. It prompted me to ask Wikipedia about bagaining. From there I took a look at The von Neumann-Morgenstern Expected Utility Theory. Pretty scarey.