It very much depends on what you mean by "devil worshippers".
There are some who would consider that anyone who does not practice Christianity are devil worshippers. Yet the vast majority of people in the world are not Christian and their practices do harm to no one.
There are those who practice Satanism. Yet many of them do not worship any deity at all, feeling that mankind is the highest form of creation. And there are those who look to Satan, Enki,Lucifer, or Set as deities and call what they do theistic Satanism. Neither of these sorts of "devil worshippers" include rape, human sacrifice, etc as part of their practices.
There are some who do practice such evil things. Think of Charles Manson for example. But they do not represent what most Satanists are like. These people are seriously mentally ill. They are as abhorrent to real Satanists as they are to the rest of us.