As a practicing Christian, I'm going to put in my two cents. From what I was raised with, we are not supposed to allow something like the occult get in the way of our worship of God. That's our personal belief. I personally think that playing a computer game with mentions of witchcraft or reading a book like Harry Potter equals entertainment, not worship. I don't take a vow to worship Satan whenever I play Sims 2 or read a fantasy book, so I don't understand DLmulsow's problem.
Of course, granted, there are people in my religion that think anything mentioning ideas outside of a literal description of the Bible is evil. I personally call these people "idiots," and I hate that people get their views of my religion from them.
However, it is DLMulsow's site and it's her right to set the rules for the site. Even if it means violating rules she already set down:
This site is friendly to most all diversity. DLMulsow is a Christian individual and all races, colors and creeds are accepted here. You are free to be different and unique. We will not tolerate bashing of any sort for individual opinions or concerns.
It is also my right and the right of everyone else in the sim community to not visit her site.

Finally, I wonder why she would make a big fuss over a video game's version of witchcraft when the same game contains the potential for these "unChristian" behaviors:
pre-marital sex
adultery
co-habitation
streaking
male pregnancy
the ability to be gay/bi/whatever
aliens
zombies
vampires
Robots and the ability to have "relations" with robots
werewolves
plant people
Bigfoot
Genies
Maids in skimpy outfits
And overall, the ability to make sims live a life that she probably doesn't approve of.
(And that's before the game mods ^_~ )