You know what we learned about selling appointments at the massage school I went to? Nothing. Why? It was an accredited, professional school that taught high quality technique, good medical knowledge, and smart
Good massage doesn't need to be sold. You "sell" with your professionalism, personality, client care, atmosphere, perks, high cleanliness and hygenie standards, quality products, etc. etc....no customer is going to come back just because you say they should! Give them a reason!
Massage is supposed to be quality, specialty healthcare, not a bottom line money factory (although it can be quite financially successful). This massage business you are dealing with sounds ridiculous. They may employee technically proficient therapists, but the rest of their business model is going to cost them customers.
You would not be rude to point that out to them.