This will hardly come as a surprise but... Satanism is still very much a taboo.
While some Satanists practice very openly, some prefer to practice in secret.
Their motivations can vary. Some are afraid to lose loved ones or fear shunning from their community. Others worry they might lose their job, and some could even risk their lives if their beliefs become public knowledge.
We may think we live in a time and age where religious freedom is guaranteed; unfortunately, the reality is not quite like that. It may apply to mainstream religions and even Wicca and Paganism, but Satanism is usually NOT included.
Why is that? Our cultures are often based on abrahamic traditions and have been shaped over the course of hundreds, if not thousands of years. Satan has always been portrayed as the Evil One, the Adversary, the Liar, the Deceiver, and the Bad Guy.
Since Satan is seen as the epitome of evil, His followers are often regarded as evil as well.
Hollywood certainly has not made things better.
There are Satanists who say that we should practice in the open because if we practice secretly, we are doing Satan a disservice.
I think it is important to remember that being a Satanist is a very individual path. We owe no one an explanation but Satan. How we practice, is between Him and us.
While we should never be ashamed to follow Satan, self-preservation is important.
Losing one's job can be a real problem, not to mention death threats.
Sometimes, secrecy can help one infiltrate places on Satan's behalf in a way that would not have been possible if one would practice openly.
We all have our parts to play, and when in doubt, turn to Satan for guidance. Let Him inspire you on how to practice. It is between Him and you.