It is my opinion that most of us in society are well informed enough to know about those implicit injustices. We read about it in the newspaper, or hear about it on TV, or in movies, or from our peers, or leaders. And then, as if by jedi mind-wipe, we just change the channel.
In my own humble opinion, this kind of outrage at the explicit is disingenuous. I think it stems from at least a faint idea, a possibility, that this person is complicit, but desperately wants not to be. I think that the way we live our lives proves how much we really care about the injustice. The outrage is just so much theater, and we're both the actors and the audience.