Earlier quoted context omitted.
This isn't about being in a public setting, this is about taking photos of people with the intention of including them in a database for later use. It can't be that simply being in public means that you give up all such rights, since it's impossible to avoid being in public. That informed consent should be obtained seems obvious -- perhaps some of those people wouldn't want their faces to be used in that way. Are the…
You are aware that just because you think something, doesn't mean it can't be any other way and that your view is obvious to everyone, right?
EDIT: I guess you're reacting to my "it can't be" comment. That was an expression of personal outrage at the idea of being placed in a powerless position, not an assertion of fact. All kinds of really terribly things are possible, obviously.