A potential client providing information for a law-firm regarding their grievance.
A patient filling out the medical questionnaire prior to their first visit to a medical practice.
Rather than having a fully deterministic form, you'd be providing them with forms that adapt to their specific issue. The data can then be intelligently stored both as JSON and a more generic record in an RDBMS.
That's just my initial thoughts.
Google has a similar project called A2UI: https://developers.googleblog.com/introducing-a2ui-an-open-p...