The thing is, if fans start taking money for fanfic, then there would be much greater incentive on the part of copyright owners to stomp on them with cease and desist orders. Even if they're fine with fanfic in principle, if money is involved, they have to protect their copyright or risk losing it. (Or so I've gathered. Not a lawyer.) So Fandom At Large tends to see money for fic as a potential threat, even in cases where, say, the money is being donated to a charity. This has caused some odd arguments where some newbie fan runs across the concept of print fanzines and has a hissy fit because OMG money changes hands. I have heard that in some fandoms the concept of commissioning fic the way you might commission fan art is starting to pop up, so maybe this is changing.

(My personal opinion is that people who pay Mark to squee incoherently are wasting their money, but it isn't the same thing as paying for fanfic. But that's just me.)

I think the demons = PMGoC thing got a boost from Angel: the Series, where there were a lot more neutral and even goodish demons than there were on BtVS. There was episode in the first season where a group of nasty, Nazi-like demons was trying to exterminate another tribe of basically harmless demons. And another episode in second season where a group of humans was trying to exterminate all demons, whether they were nasty or harmless. Plus you have a main demon character (Lorne) who's coded gay, and was a very popular and sympathetic character. But it doesn't work for demons overall.

BtVS's scorecard on racial issues was Not Good. :P