This story is actually more important that just pointing out liberal hypocrisy. On the show this wee I pointed out the media template of "black good, white bad" in covering racial conflict that goes back to the 1950's. That is to say that in the media's world, the black always wears the white hat when there's a racial conflict(Trayvon Martin). An extension of that is the belief that liberals, simply by their very nature, cannot be racist. And the SPLC has extended that belief further; the left isn't capable of hate.
And as for the notion that "the SPLC only deals with hatred of people based on class characteristics," what are you kidding? They hate the upper class because they're the upper class! The proclaim it proudly. We ARE the 99%. And they've made their hatred of the 1% crystal clear. But don't look for the SPLC to concern itself with people who hate the rich. They might align themselves with people who hate the rich, but certainly won't be concerned about them.