It's always been my experience that such people use this as a way to “hate” and still feel clean afterwards. Now, the Rev. Br. Tobias Haller has posted a penetrating entry on this topic with Enough of Hate:
It is impossible to “hate the sin” apart from the sinner, as if sin had some reality apart from the desires and actions of fallen human beings, as if you could somehow extract the sin from a person and vent your purifying fury upon it. Such a notion is very far from the Gospel. What is worse, those who begin by “hating the sin” in this abstract way soon will come to hating the sinner in a concrete way, as indeed they must, since the one cannot exist apart from the other. And when those who legislate what is sinful have sufficient power, we have seen what results: the auto da fé was intended to save the souls of those repentant heretics being burned alive.
Amen, Amen, Amen - What I tell you three times is true.
[with thanks to Fr. Jake]