"In the best case the programmer and the company will both think they are getting a good deal."

IMO that is far from the best case. That allows "ignorance is bliss" and, at the other end of the malice spectrum, for one party to be taking advantage of the other.

I once sold a rare trading card for $50. I thought I was getting a good deal, the other person knew it was worth much more than that and thought they were getting a good deal. Was this situation optimal?

I once sold a laptop to a person over craigslist for a fair price. He thought he was getting a good deal as well. When I got home I discovered that model had just been obsoleted and so a brand new one was as cheap as the used one I'd just sold. Was this situation optimal?