I recently picked up the Black Pearl from Walmart.com, where it was on sale for $81. It arrived today, in completely destroyed condition. The box it was packed into was roughly the same width and length as the BP box itself, but was also easily five times its height. When it arrived at my door, it was completely open and filled with leaves, and the Lego box itself was damaged and torn open on one side, since there was zero packing material to stabilize it inside the far larger packing box.
To make things worse, the delivery folks (USPS, I think, any trace of the shipper seemed to be destroyed) didn't rang the doorbell (doesn't surprise me, or I would have outright rejected the delivery), so I got it after it had started to rain -- the whole bottom of the box was filled with water, the Lego box itself was sodden, and the moment I picked it up, both boxes fell apart.
I bundled the whole thing up into a garbage bag, checked which local Walmarts had it in stock, drove to the closest one (40 minutes away), and went to customer service returns. They explained that since I had gotten it from Walmart.com and that the problem was shipping at not Walmart, that I needed to deal with it online. I pointed them at the policy on their website which says explicitly that items bought online can be returned to a retail store, and the fact that if Walmart hadn't so carelessly packed the item, it might have had a chance of survival. They did agree to issue me a store credit, but they did not actually have it in stock (there was no sign of PotC sets anywhere, including in the clearance aisle). They did credit me the full item price I paid online (as opposed to the $69.99 price they had in their own register), but not the shipping and handling. (They were at least polite and sympathetic.)
I picked up the Ninjago Destiny's Bounty instead. They refused to honor the online price for the item, though ($10 more in-store, although I guess if I had really wanted to take the trouble, I could have purchased it online from my phone, and used in-store pick-up, so that's kind of absurd).
I have learned a valuable lesson about not shopping at Walmart, and I ordered the set from Lego directly.
If you're ordering your BP from Walmart.com, be aware that their shipment method is unlikely to get you a box in pristine condition.