I use a case for grip, not for the protection it provides. I'd be dropping this slippery device pretty often otherwise. I haven't been able to go case-less since the days of the iPhone 4.

> Apple fixes or replaces it for free

Where? In the US they charge $29 and up for repair with AppleCare+. $29 for the screen, $29 more if you damage the glass on the back too. $99 if you damage the camera or anything else that requires replacing the phone altogether.