Why does Hollywood hate redheads?

Neil Patrick Harris of How I Met Your Mother was on the Craig Ferguson show this morning. I watched a couple of episodes of that sitcom its first season, but it rarely if ever made me laugh, so I haven't watched since.

So maybe this is old news, but seeing a clip from the show, during his appearance, was the first time it really sank in that Alyson Hannigan had seen fit to dye her lovely red hair black. It took me a moment to recognize her.

It's a conspiracy, I tell you. Probably some sort of "red-state bashing" thing.