I want a super thin to protect from key scratches or other inadvertent rubbing. I want to be able to lie my phone down on a table without worrying about what I put it on. And I want to feel like I'm going naked. That's what a super thin is for. It's not for everyone, that's for sure. But it sounds like there's a pretty sizable number of folks on here that fit the profile.
Like I said earlier, not for me to judge, but I was like you back in the day and letting the phone go without plastic protectors set me free and allowed me to have a better experience without the dulling of the screen, bubbles under the plastic, etc.
Regarding lying your phone down, you should consider a bumper for that reason now with the iPhone 6 as the protruding camera bezel is going to be problematic for those who eschew a case that's at least as thick as the lens is tall.
BJ