You say, "I don't like the surveillance state, in particular the ubiquity of cameras in public open spaces where there's no compelling reason." You are assuming there is no compelling reason because you do not personally know what that reason may be. Someone, somewhere, thought they had a compelling reason to go through the expense and hassle of developing and installing the surveillance system. It wasn't just "IDK, it's kinda neat".
It's clear from the gaping, empty space between our understanding of these systems and the desire of institutions to have them that something must be filling it. Whatever that "it" is should not be hidden from the public and communicated clearly, and not just hidden in a TOS-like document locked in a room with a tiger in the basement.