It's not uncommon for professionals in many fields to offer free services. Doctors, dentists and optometrists often participate in health screenings, and lawyers sometimes offer pro bono services. We see something similar in real estate. But while such limited services and information are free to prospective clients, they are not free to brokers.
Information takes time and skill to prepare and present, and time and skill have value.
In effect, CMAs and other information are often loss leaders, services provided for the purpose of introducing yourself and your services, a way to stand out from the crowd, and a form of promotion. Moreover, much real estate information must be given away without charge. In a competitive marketplace, if Smith charges for a CMA and Jones does not, Smith will soon be out of business. What we can see is that there is a purpose and business necessity to free services. Rather, it concerns the matter of perception, being able to deliver what was promised and what consumers expect.