There's a vast amount of confusion in our society because the megaphone is routinely seized by hate-filled pundits who denounce everybody they hate as being driven by hate. So, the concept of a "hate crime" is murky, to say the least.
But, society does have an interest in deterring through harsher penalties crimes not of passion but of premeditated malice, cold-blooded crimes that occur only because of animus toward groups. Quite possibly, "hate crimes" is the wrong term completely for these types of actions, but that seems to be what we are stuck with.
For example, by way of analogy, I particularly loathe witness-murdering.
Consider two homicides:
At minimum, society has an interest in keeping stuff like this from becoming fashionable. Say, or example, a third person videoed the attack on Yglesias, and the whole point of the attack was to have something cool to post on YouTube.
Of course, all this logic chopping isn't very relevant to how most people think about hate crimes, which is in Who-Whom terms. Matthew Yglesias is extremely well-plugged into the world of Washington punditry, but it doesn't occur to his peers that this attack on him could possibly be a hate crime ... because he's white.