They're also superior (and less stressful) for a certain type of person - for example, my mother appears to be slowing down a bit, mentally, as she gets older, and a chat bot would be a lot easier for her to navigate over a phone menu, because she has time to read it and think about it without feeling pressured to key in a response before the phone menu times out. And she doesn't have to worry about forgetting what the phone menu said because, hey, it's all on screen.