I have done free sessions for people and done paying sessions for people. I see no reason to not offer free Reiki but I was also taught that charging a fee of some type keeps the energy balanced between the healer and the person receiving the session. It is up to you but I know for me I like to offer free sessions to friends and family but I do charge when others approach me that I do not know. It may seem unfair to some but there have been times where my friends have given me a small fee or we have bartered for sessions/services.