Some believe that in Reiki, there should always be a payment because it means an exchange of energy. One should pay for receiving Reiki because this way there will be no one-sided energy flow. Many people think that if this is not done, then there will be problems in the healing process. Compared to the other ways of healing, Reiki requires this exchange of energy because in other ways, there is no flow of energy. So Charging fee becomes almost a necessity in case of Reiki.
But there is an issue regarding this belief and many want to know the origin and reason of this belief. It was originally mooted by Dr. Usui who began charging after his experience with healing to the beggar people. Later on, Mrs Takata used this as a rule in her training. She also gave examples of Hayashi Sensei who was also in favour of charging always. But there are instances which seem to convey that he did not charge any fees from people because many were too poor and could not afford healing or any regular medical care. So there are contradictory views on whether Hayashi Sensei charged some amount of money as an exchange of energy in return of the healing which he provided to people.
Despite all this, it appears that these instances are not the basis of the concept of charging money in exchange of Reiki energy healing. In Reiki, there is a ritual called Reiki Kohan in which blessing is received from the practitioner or Master which is required to raise the power and effect of the healing.
The reason behind the payment concept of Mrs Takata is not known very clearly. She was strictly in favour of charging some amount of money from people but it is not known what the reason behind it was. She also used to mention Dr. Usui and Hayashi Sensei as the beginner of the concept and system who were the two important figures in the field. Among the two, Dr Usui can be termed as the founder of modern Reiki who had revived it after a gap of several hundred years.
In case Hayashi did not charge anything from people then it can be conceptualised that paying is not a part of the healing system. There seems to be no binding on this aspect and it can be safely assumed that the concept of energy exchange as a reciprocation was not the part of the original Usui system.