Sold a tie to someone and I shipped it in a small flat rate box. The buyer lives less than 90 minutes from me, so it arrived promptly. The tracking info shows that it was delivered on the 19th. The buyer messages me on the 29th claiming they never got the tie. I ask them if they called the post office, because the tracking info shows that it was delivered. They are basically belligerent, claiming that I committed fraud, etc. They leave negative feedback. I call eBay and get a bunch of bullshit about how they can't remove the feedback unless the buyer opens a case and it's escalated to eBay (and even then, the feedback might be removed). For shits and giggles I ask them if I issue the buyer a full refund right now, will they remove it. Nope. I guess eBay doesn't find it a bit odd that the buyer didn't open a case (obviously because they got the tie). According to the eBay rep, eBay is responsible for issuing the refund in a case like this (item was shipped to the address in the system, but was "lost").
I guess the new eBay policy is that a buyer can leave you negative feedback for absolutely no reason and eBay is perfectly fine with it.