I like using my phone (and the ones I've had in the past) without a case. Sure, if I had a case on my G2 years ago, it probably would've never broke.. never had an accident after that, either - but cases for a lot of Android phones suck. They either have bad quality or they have an ugly design. I have a hard time finding decent cases that don't have silly or unnecessary graphics.
For something like an S7 Edge, I would be anxious all the time using it without a case since the glass is exposed a lot (on both sides). Same with the newer S8.