Thinking about it, it's quite disgusting really. Other retailers don't allow certain items to be returned for hygiene reasons. Let's talk about earrings, so someone can wear a pair of earrings for 3 months, decided they're not for them, or find that they irritate them, so they send them back after giving them a quick wipe, and don't tell me they don't send them back out to another customer (what the eye can't see!). Bedding? Doesn't even bear thinking about, although it would be a lot harder to pass off 3 month old bedding as new, but I'm pretty sure it's been done! As Boffy said, you'll get a flea in your ear and a fraction of your money back, so from the customer's perspective is it really worth the hassle?
I would say it's great for skincare, to be able to recoup some money back from a really expensive moisturiser that doesn't suit your skin, or to be able to return an expensive pair of shoes that were comfortable initially but are now excrutiatingly uncomfortable, but in the grand scheme of things who wouldn't want to pay less in the first place?!