The secular problem with this: How do we make sure that people aren't forced into this?
What you're really getting at is being forced into it by humans and/or groups of humans, and when it comes to that, you'll have to delineate your categories, identify incentives, and then either counter those or eliminate them.
Two to consider would be greedy relatives looking for some kind of inheritance and health insurance companies hoping to avoid another million dollars in keeping someone alive.