Imagine all the merchandise that would be returned, both used and unneeded after Burning Man. People would buy everything and just make a return.
I had a bike that had defective gears that I bought at Walmart. It was playa covered and defective. I just wanted a replacement, so I deplayafied it and then bought a brand new one several weeks after the event. I returned the one with bad gears with the second receipt---dated long after the event was over. No problem and I had a good bike.
Walmart has made an art out of selling cheaply made products, for low prices. If an item doesn't work, they really need to honor the warranty--one way or another.