A few thoughts here.
Stern has an MSRP that they list to the public. They also have some version of an MAP (minimum advertised price) that they do not list to the public, but they require of the distributors. In addition, they occasionally (Beatles and possibly others) require distributors to purchase a minimum volume of games in order to obtain the limited edition games.
These all impact a distributors ability to make profit. If I understand correctly, they leave the high end open for distributors to make profit as the market allows. Prices are driven by things like services provided by distributors, geography, supply, demand etc.
Correct me if you know differently. No one called me to explain the policy. I just paid attention and have made a few guesses here. The bottom line is that I, like many others, want a good price. I also appreciate that the distributors need to make a living.
Distributors are not fat cats riding home in the back of a limousine. These are working men and women running a business. They are human just like the rest of us. Good ones float to the top. Pick the one that works best for you.