I'm not directly disagreeing with you here or putting words in your mouth. I realize you are not saying safe spaces should not exist. Instead I want to make the argument that having safe spaces is reasonable.
People make safe spaces _within_ universities and other institutions for the same reason some combat veterans with post-traumatic stress disorder put up signs asking neighbors not to set off fireworks[0]. It is to avoid triggering people that have have experienced serious trauma[1].
For instance using the combat veteran example, it would be unreasonable for a veteran to attend a fireworks show and then complain about the fireworks, but if this same combat veteran was attending University and it would be reasonable to ask the University to provide a safe space away from fireworks or other triggers -- sound proofed dorms if students are constantly setting off fireworks.
There is a big difference in intention between 'safety from conflicting points of view' and safe spaces. Although a safe space sometimes requires limiting certain discussions (a person who was sexuality assaulted might be triggered by discussions and depictions of sexual assault).
[0]: http://www.militarywithptsd.org/fireworks-triggers-ptsd-and-...
[1]: http://www.nimh.nih.gov/health/topics/post-traumatic-stress-...