Because it matters? Because it's the very reason this thread exists. It's the primary line of attack in America on any sensible set of policies that anyone left of Ayn Rand proposes, so it should be included as a discussion limitation.
What are you talking about?
You made a post where you argued about Nazis not being marxists when that comparison hadn't been made in the first place. Is it really that hard, if you're going to respond to posts, to respond to the argument actually presented rather than just deliberately misrepresenting it in order to construct some pointless straw man argument?