I agree that privacy must be respected in private places. For public places you should be free to photograph anything you want. In The Netherlands this is part of the "freedom of speech" law.
But I also agree that you can respect someones wishes, so when somebody asks me to delete their photo I will. When they demand me, than it is a different story
We think the same :-) the thing is, in this particular case, that the title is "No photo" so this becomes the main subject. May be posted to have reactions? I don't know :-)