There is no point in comparing retail price to retail price in the CE market. Nothing sells at retail price unless it is brand new, or ultra-hot or both.
The prices I quoted were from real places. Apparently discounting is heavier on the Pioneer. That may have to do with the fact that they chopped the introductory retail price from $10K to $8K. Without knowing dealer cost/mark-up/margins, there's no way of knowing how deeply they can discount something and still make the money their business model requires.