Outdoor activities or any hobby that requires you haul around a lot of gear
Indeed, this is something that gets totally missed by advocates of on-demand self-driving yadda yadda, because they live in densely populated cities and socialise and get entertainment almost exclusively online. That demographic is overrepresented on HN. Most people who own cars who might use them to commute during the week use them for fun stuff at the weekends too, for which glorified taxis are just not suitable.