And if you think that's what it's about, you are too.
Let's learn together, shall we?
First of all, yes, some people who claim to be Satanists do worship a "devil". But that's not a true representation of the religion. It's a broad representation of a group of Western Religions that all have diverse beliefs.
There are two main types- theistic and atheistic. Theistic is the one that isn't a good representation and gives them the bad name. They believe that Satan is a god to worship, blah blah, blah. This, however, doesn't make them evil.
The true Satanists believe that Satan is not a deity, but a word or symbol to represent the nature of who we are at birth- people who feel no battle between thoughts and feelings, and who do not embrace the concept that we are souls trapped in a body. Satan represents pride, liberty, and individualism.
Of course, Christians took that as an attack on their god and labelled an anti god Satan. This god, in case you didn't notice, doesn't give you individualism, pride, and especially not liberty (from what I've experienced personally, so please don't take that as offensive). That's how the devil became Satan. Because of a small rejection of what someone else believed.
So, cough cough, why must you be hating on someone with opposite beliefs? It doesn't make them a bad person to believe freedom and pride, does it?