I cannot believe, that this kind of thing still excists. The facts are allways incorrect and all the reasoning pulled out of randomly.
I remember, when I started to play when I was just a kid (11 years old) some of the people around me did think I was invovled in satanism and/or Satan worshipping.
You might want to check this site out, but don't let your blood pressure go too high.
And remember (according to that site) what is the real purpose for RPG Cons:
"Now, games give explicit instruction in the rituals and methods of the occult. Indeed, gaming tournaments are prime times for occultists to find 'recruits' with exceptional ability"