"In some states, you must give written consent before receiving a massage - every time. Without written consent, the massage therapist could potentially be charged with assault."
We all hate paperwork. Not only do we hate filling it out, those of us on the other end hate dealing with the filing, organizing, etc. Unfortunately paperwork does exist for a reason. Sometimes it helps up learn information that is needed, and sometimes it protects us and our clients. For example, having a client sign a page understanding a business' protocols and expectations protects the client in that they understand what exactly they are receiving, and that they understand the rules and expectations of the office. The therapist is also protected in that is the client tries to break those rules, the therapist is protected in holding up whatever consequences are set forth for those rules being broken.
Many people will come for a massage just looking to relax and escape from the world for a little while, and the last thing they want is to have paperwork shoved in their face. Once again, this is for the protection of both the client and the therapist. Some therapists like to have a daily record of what the client is looking for, what they need, and what conditions they have or have changed since their last appointment so they can treat them properly. In some states, this is not only useful, it is the law. Since Massage Therapists are putting their hands on another person, and often asking them to do things such as disrobe, even though it is for a purpose, the therapist still needs proof that the person disrobing and being touched has given their consent for the therapist to do these things to them, otherwise, the therapist can be charged with assault for putting their hands on someone without consent. In some states, verbal consent or the fact that they scheduled the appointment and showed up is enough consent, but other states want to see it in writing. And even if it isn't ordered by the state, many therapists want the paperwork (once again) to protect both the clients and themselves. This is also another reason that Massage Therapists shouldn't work on people who are intoxicated or under the influence of drugs. In an altered state of mind, they are unable to give informed consent, and could accuse the therapist of taking advantage of them.
Even though Massage Therapists do their job for the betterment of their clients, and to help people, they still need to protect themselves. From a legal standpoint, paperwork with a signature is one of the safest ways to do that. So even though we all hate dealing with it, it is one of those "necessary evils."