My basic thought on the subject is that Ebay is in the wrong. If someone sells services and items like this, and people buy it, there is nothing to complain about, especially if those people are happy with the results. Those who are not, well that's the issue when you buy a service or non-returnable/refundable item in general.
Let me put it this way, spellcasting and such can be fun, even for those who don't believe in it, there is a reason why it thrives at fairs and such, and you'll find little new age shops and such selling services here and there, and people doing this kind of thing at fairs. At the very worst you can say hiring a psychic to do a reading is for the entertainment value. Ditto for buying a ring or something with a story behind it you find interesting. On a lot of levels that's what your seeing going on in E-bay. Buying a reading or spell from someone, is no worse than walking into a New Age/Occult shop and buying one there.
The only thing that surprises me about some of this is that I'd think part of the business would be the people doing this to have a webcam and to produce a video (even as just a file) of them doing the spell or whatever.
Also for the record, if the person buying believes it worked (even as a placebo) so much the better. I mean if your werewolf transformation spell give you the confidence to improve yourself, and your happy with it, who cares if it was real or not assuming you believe it was and it for all intents and purposes works?
Ebay DOES need to police scammers and such, but I think they have been getting kind of ridiculous in some of their policies, and too heavily regulated by external forces (which is another discussion entirely). Maybe it's just me, but this seems like an attack on novelty businesses and services.
Speaking for myself, it would be great if magic existed, but I don't think there are easy answers to people's problems, if there were, everyone would use them, and no offense those with this power wouldn't have been overrun by whatever group they blame (Christians, Romans, Nth Dimensional Insects that later disappeared). That said it can be a lot of fun, I even got myself a set of Tarot Cards on a whim, though I haven't yet put the time into learning how to use them. Leave the people who do this kind of thing alone, there is nothing wrong with a bit of adult make believe, and if that's a fun way for someone to spend money, let them do it.