Color me old fashioned, but I don't want car service at my house for a multitude of reasons. And of course anything needing a lift, body reapirs etc. are out of the question.
The mobile service idea is fine, and certainly can work for part of the service, but beyond that, Tesla needs a scalable and sustainable solution to selling and servicing cars in all markets, in all reasonable locations.
Traditionally this has been achieved through dealerships.
As said, even Apple - which was brought up as an example in this thread by several people - doesn't attempt to do it all by themselves. They have the stores as the halo project, and catering the biggest market centers, and then a third-party network to scale the volume and the locations.
In the end, those people queueing for the next iPhone, only a small portion actually do so at an Apple store. Let alone those getting their broken iPhone screen fixed.
Tesla already does body repairs at third-party locations, of course. Expanding this to cover all maintenance of the car would make sense. And even though some claim otherswise, many Teslas do need a lot of it - warranty fixes for example...