This is a resource allocation problem. People (whether individually or collectively) work to create things of value and direct some percentage of that to medical treatment. If that is wasted in rare cases, that’s unfortunate but we accept some amount of imperfection. If it’s wasted in a lot of cases, many other people will go without needed care who didn’t have to if we allocated that spend more effectively.
How could not money pay part in this? If the continued care costs, let's say $10,000/month (not unusual for the US) and you have 1:1000 chance to live that month, it means this month has cost $10 million dollars. Who is going to pay for that? In fact, taking all this money for yourself, the healthcare for other people will need to be reduced which can lead to shortened life expectation for those people.