Doctors are a special case in that, for better or worse, you have to go through them to get a lot of medicines. (And IMO by and large that system makes sense.)<p>Outside of Bloomberg terminals which are a relative high-end niche, most individual investors get their research and financial advice bundled with transaction and management fees.<p>I basically agree with your other points. But, relatively speaking, things like fashion advice and personal trainers are very much a niche--and, as you say, based on very interactive service. And pretty much for comparatively high-income individuals like other personal services.