Depending upon the Type of Satanist, yes, they are often just people looking for a high "Boo-Factor" (A term made-up by many of the early followers of a musical Genre called "Deathrock" (it's more public name is now Goth, although that is like comparing a chain saw to a kitchen pealing knife - the "Goths" are the kitchen knife).

Many Satanists, especially those who hadn't really read much of the published Satanic literature would just make something up themselves and it was almost always based in Christian motifs and archetypes. The two institutions who have publicly claimed the title of "Satanist" (The Church of Satan and The Temple of Set) both reject any and all of Christian Theology, Motifs, Archetypes, Symbolism and Characters as being ingenuous and twisted archetypes of older more healthy god archetypes (If you read Jung and Joseph Campbell, this is not uncommon for a rising religious paradigm to hijack an older competing paradigm as its bad-guys)

As Phil has suggested, maybe a front page post will come in handy. It should be recognized that some Satanists happen to be very rational people. They are just using the symbolism to manipulate their environment (although most of the more mature ones have found more mature symbols with which to manipulate the environment and their peers and subordinates).

The types to which I was referring in my post were the Christian Satanists (people who are worshiping the Christian version of Satan), which is just as bad as worshiping the Christian God. Both the Christian God and the Christian Satan are required for that mythology to be complete.