I agree that this case isn't just about money (from the British side), but at the end of the day there will ALWAYS be a decision made that is based on financial considerations.
One thing that always bothered me about this case was that the hospital had no qualms about overruling the parents in medical decisions that didn't even involve the hospital. Who could argue against the wishes of the parents to simply bring the kid home, if he is going to die anyway?
At the same time, we should recognize that there is definitely a gray area between parental rights and the best interests of a child -- and it often involves medical care for children. Parents get prosecuted for child abuse in the U.S. all the time in cases where they made decisions related to medical care that endanger the health of the child. Most states have religious exemptions written into their child abuse statutes, but I believe 15-16 states do not.
Children have traditionally been thought to be under the exclusive authority of the parents. In the last century the “best interest of the child” argument has become a factor. I googled that to see what is the constitutional basis for courts to get involved and override one or both parents. While not a very thorough search on my part, it seems to be derived from judicial rulings that are largely done in the last thirty years. Of course in family court, best interest goes back further when men get their parental rights taken away so the mother can exert near total control.
Give courts enough time and they become the law, not interpreters of it.