It is not so strange that tourists have no notion of this, above all, it is understandable that they rely on the guide, there is nothing wrong with that.
It is the guide who is not worthy of the profession, but yes TIT anyone can call themselves a guide, there are not many professions in Thailand that are protected and knowledge based, unfortunately.
Actually, it is not worth the mention, after all anyone who has been here longer knows how things can get, but for the tourist it is a different story, another non-positive experience with LOS.