I think you'll find this sale is more to related to the public requirement and market for the exact term. There's sometimes little trust in diagnosis and medical outcomes these days. So often you get to see many doctors, specialists etc and the outcomes can lead to a sense of confusion, complexity and even possible negligence. Individual medical histories being digitized are far more available to that individual.
You authorize the access to a specialist service (probably high fee) and your effectively being offered a full second opinion on your medical history. Patients want to be fully informed these days and some medical services are slow to catch-up with this requirement.
I know if i was to be offered a full medical history review - I'll take it. Of course this is the sort of service that it's the older generation are looking for. And as mentioned there is the post-death negligence angle, again relatives are not always satisfied with a common blanket-term on a death certificate.