They're more common than you think. There was a guy in an apple store near me over the weekend who I overheard requesting a replacement for his scuffed iPhone 5. I was browsing cases when things got heated and it became clear why the manager was refusing to replace his phone. It was his 10th attempt to replace a phone for cosmetic defects.
At the end of the encounter, he smashed his phone the floor and stormed out. Then stormed back in and picked up his phone and tried to type something and obviously it didn't work because he tossed it on the floor and stormed out again still in a chimp rage.