Next you say the "fraud" is not the religious beliefs, but instead the "claim of medical benefits." Medical benefits provided by God certainly fall under the umbrella of religious beliefs. Religious beliefs, stated as such, are not actionable as fraudulent misrepresentation.
It is certainly not actionable under either criminal or civil law to represent that God can heal, or that one is going to wish real hard for God to heal someone.
If faith healers said something like "In 10 minutes, God will perform an appendectomy on you, if you give me $100" or "God has transformed this Kool-Aid into heart medicine, so you no longer need your Lanoxin" you could certainly charge them for practicing medicine without a license.
However, the claims are, as I understand them, the following.
1. God can heal sickness. This obviously follows from the definition of God as all-powerful, and able to do anything not tautologically phrased.
2. People can certainly pray to God, and one of the things they can pray about is for God to heal them of their afflictions, which he may or may not do.
3. People may pray to God to heal the afflictions of others, and according to scripture, placing their hands upon the sick person while doing so is a practice that may be employed.
4. Even through the prior doctrine is part of many religious denominations, most priests and pastors avoid the can of worms which a healing ministry entails, and limit their attempts at healing to praying and conducting religious services for people who request it
5. A very small number of priests and pastors will make touching people while praying for God to heal them a public part of their ministry.
As long as no medical claims are made, people aren't told not to see their doctors, no one is told to stop taking their medicine, and no one is subjected to the practice except those who believe and show up and ask for it, I think it falls under the scope of a protected personal religious practice.