Just like the brony thread.
There is a sort of knee-jerk response to blow up the deviance and misanthropy of an out-of-the-norm interest.
For the record--I don't have a waifu or nurture those sorts of feelings. I do however think the whole "she is my waifu she is pure and innocent she will never betray and I will not act in a lewd manner with any other 2D or 3D filth" is funny. And though the harem/romance stuff I've seen wasn't all that great (Tenchi Muyo from what I remember, Infinite Stratos) and I'm not into the genre I think it's harmless to root for a "best girl" to win. I rarely watch it myself, and never read manga, I don't like comics of any sort but I do like reading books.
But come on. Why does someone who--to take it as far as having the anime pillows and shit--have to be totally socially maladjusted? Maybe they have friends? I gave anime nerds a hard time growing up (well, I did that to a ton of people), and in college I got to know more people who were really into anime, by checking out an anime club every so often. Some of these people have lives, jobs, and can drive; there are indeed girls who are into anime figures. Sure they may take it to a level that is distasteful for some (I've found it annoying to see people wearing cat ears and saying nyaa~) but the ire is so disproportionate that I can't help but be disappointed.
To be clear--there is a decent boundary covered by the fact that some people find anime, manga, figurines and such to be a stupid hobby or not altogether interesting. What I'm against is this ease at which these people are labeled as subhumans and different from normal people. Maybe this is just the growing pains of accepting anime watching into the broader culture, but it sucks.