There will always be frauds but with our technology now, less so. I saw more "I can see the dead" types than faith healers in the last decades.
Sometimes the power or faith or thinking can make you feel better...I worked at a pharmacy where drug studies were done and placebos, fake meds, had to be used by some and the real drug for others. Sometimes just thinking they were getting the real drug made some feel better depending on the disease or ailment. It doesn't cure but can make symptoms better.