I'm not addressing the wisdom of doing it, just the feasibility!
If a seller thinks he is losing business because of having to sell at MSRP, it may be beneficial. For example if a customer is ready to buy a complete system with multiple speakers and subwoofers, and the last item is the AVR with MAP constraints, and he realizes the AVR is going to exceed his fixed budget (good example is a student with a tax refund check) it may be worth pulling the "open box" trick to close the deal.
But I am pretty sure I can give you a better example:
https://www.ebay.com/itm/Denon-AVR-X4400H-Black-9-2-Channel-Network-A-V-Receiver-OPEN-BOX-PERFECT/312218588465?hash=item48b1ad9531:g:TbUAAOSwFvZbojWQ&frcectupt=true
So these guys are selling "open box" X4400H's at $800 each. That is no super deal since it is last years model, but I recall $900 as the going price for these NIB after the 4500 came out.
However, if you look above the "Buy It Now" button they show 8 available and 319 sold. How does someone end up with 327 open box AVR's? I could be wrong, but it seems likely these guys are going for high volume sales to cover the losses in profit. You have a better idea of how the numbers might work, but at 320+ units sold I bet they are making money.
Obviously, Sound_Distributors is not a brick and mortar operation and I appreciate that a B&M operation is not likely to see the volumes to readily justify doing this. However, I believe one of the original poster's messages involved his asking someone up the chain about offering the items at a discount as if he had occasion to
want to do that!