An individual 'satanist' is a human being of the typical mixed morals nature. Some are more evil than others. Some, no doubt are good individuals who pay taxes, mow their lawns, give to some charities, are kind to small animals and always send a card on Mother's Day. Some, no doubt are foul villains who cheat, lie and steal every chance they get.
Pretty much the normal human spectrum.
However, and pay attention to this distinction, by being a 'satanist' of any degree, one supports Satan and the anti-God and Jesus movement. That is an evil deed (action). To be fair, the degree of support for Satan varies with the individual. Some might be surprised to hear they are anti-God and some are probably proud of it.
Reeniee said:
If so, how and why is it different to followers of any other religion we believe to be false?
I don't see any difference at all. Any religion which diverts people from the Saving Grace of God through Jesus is propagated and underpinned by Satan. Even if those religions do 'good works', which is not uncommon.
Reeniee said:
Could it be because we believe Satan exists?
I'm not sure what you mean by this? Specifically, could WHAT be because we believe Satan exists? Just for the record, Satan exists. The Bible is full of references to Satan, either by name, title or function. If one believes the Bible is the message of God, then one must accept Satan's existence.
Reeniee said:
My instinct is to say that Satanists are evil, but I'm not sure that's actually consistent with my view, or it might even be hypocritical.
Does what I say in the early part of this response give you any 'relief'? Satanists support evil, but may not be overtly evil.
Reeniee said:
And if we do decide they're evil, what does that mean in practise?
It means they are in the same condition as any other non-beliver. They need to surrender to God and be forgiven.
Reeniee said:
Avoid Media Produced by them even if their beliefs aren't the subject matter?
Complicated subject. I would not give money - even purchase money - to an organization or support organization who's primary allegiance is to Satan.
If the product or service to be purchased is generated by a person who is a Satanist, but sold for personal support, I [just my opinion, not particularly to be followed blindly] would consider that a different matter. Without some contact, one cannot ever be a witness to anyone. But I would - and recommend - much prayer before making a commitment. Do only what God agrees with you to do.