It is not unfair to ask a therapist anything. Even those guys say a client can ask them anything. They may not answer -but the asking does not hurt a therapist. Second not everyone is going to want do anything with those guys. Third keeping in touch with a therapist does not equal therapy for free. I kept in touch with the first one that I tried when I was in my 20s. We shared a hobby and got together a couple of times a month. No free therapy was involved.