It's funny; some brands get shat on for charging over sticker (i.e. markups on Highlanders, Tellurides, etc.) like they're out there murdering people, while Porsche gets away with it through franchise stores.
In speaking with my Lexus dealer in the past couple of weeks, they are prohibited from corporate for selling any used inventory as retail sales for a dollar over MSRP, regardless of demand. So if they were to accept, say, an IS 500 Launch Edition or even an LFA on trade, they could only auction it (where a third party dealer undoubtedly would snatch it up for well over sticker) and not sell it to a retail customer.