The "we've all done worse" argument irritates me because it supposes this girl did something wrong. Fuck off, prudes
It's only wrong if she's ashamed of it.
She can come out screaming with both hands giving the two fingers to the world for all I care, and good for her if she does.
But my guess is that she was very drunk/drugged and regrets this immensely.
Some people want to fuck in the open, there aren't many of them though.