> IIRC, the primary drug in Ayahuasca is DMT, which can be acquired other ways (that are less likely to make you puke) than drinking their jungle juice.

I strongly suspect that with psychedelics, the context in which they are taken is far more influential on the kind of experience you have than the actual neurochemical effects. A sugar pill given to you by a man in a white coat and a soothing bedside manner is going to have a bigger effect than the same pill given to you by your next-door neighbor the handyman.

The service these fake shamans are providing can be of value even though the shamans are fake.