Satan is the best friend the church ever had. If it wasn't for the belief in the big evil Satan the church would be out of business.
Assuming, of course, that your view is that the church is merely a business. Some are, no doubt about it. But there are different definitions of what a church is. One definition is simply a religious organization that propagates certain doctrines and practices. Some of those "churches" are far more focused on worldly than spiritual things, and there's no question that in some traditions, Satan has been used as a bogeyman to frighten people into submission. That is not, however, the Biblical definition either of the church or of Satan.
In the Bible, the church is the "body of Christ"; in other words, the body of believers who act in Christ's stead on earth.They receive their teaching and power through the Holy Spirit, and in no way need to rely on the presence of Satan to validate what they do. Satan is merely a rebellious angel, under God's judgment, who works against God's purposes while he is allowed time to do so. He has no power over real Christians. What power he may give to his own followers is ultimately to their detriment. And he is not the mythical king of some underworld hell. He will be among those punished by God when God's time for it comes.
In making your cynical comments about the church, you are really attacking a caricature of the church, not the real thing. The true church of Jesus Christ is not a dog-and-pony show where people are frightened into submission with tales of red-suited devils, pitchforks and torture. It is a powerful spiritual organism operating on Christ's behalf on this earth. I assume that it suits your purpose to mock religion, again as a way of discrediting what others believe so as to make it easier to persuade seekers to your way of thinking. Such tactics are misleading and dishonest. If you believe Satanism is the best way of life, then prove it so by honest, reasonable argument, and not by mockery and verbal tricks. Until you do so, I would caution seekers to beware your deceptive tactics - exactly what we might expect from a follower of the "father of lies".