i am more "uncovered" than i am covered. currently using an Otterbox Commuter while at work (Construction Industry) but the minute i am going home until the next morning, and weekends, i am completely uncovered (with the exception of screen protectors on both sides)
like sort of mentioned already, when you have a device without a case you are in a different state of mind.. "Super-Aware" if you will. there are certain things you will do or not do while not using a case. for example; i will not check emails, texts, notifications etc.. as soon as i receive them. i do it at my own discretion. this equates to a lower amount of times i will be removing the device from my pocket which decreases the chances of something happening
most of my friends that work in office have no case or screen protectors and i have yet to hear of any horror stories. does that mean they have been lucky? no, more likely they have been super-aware. of course i have some friends that do it knowing that worse case scenario they will just buy a new one outright
this is just like anything else; if you have something nice and want to keep it that way then you are going to protect it. does not mean you have to. plain & simple