The rule is, don't allow someone to kidnap a baby. To ensure that this rule is not violated, people aren't allowed to pick up babies and just leave.
Whether it is a case of kidnapping is entirely determined by legal custody. The trial would go something like this:
KENNEDY LAWYER: "To whom does the responsibility of payment for services rendered ultimately fall?"
HOSPITAL ADMINISTRATOR#1: "The recipient."
KENNEDY LAWYER: "And if the recipient is a small child?"
HOSPITAL ADMINISTRATOR#1: "Then it would become the responsibility of the child's legal custodian."
KENNEDY LAWYER: "Thank you. Next witness, Your Honor."
[INTERLUDE]
KENNEDY LAWYER: "If Mr. Kennedy's insurer were to deny a part or all of the claim on his child's medical services, to whom would send the remainder of the bill?"
HOSPITAL ADMINISTRATOR#2: "Mr. Kennedy himself."
KENNEDY LAWYER: "Thank you. No more questions. Your Honor, I suggest that the case against my client be dismissed now so that we can expedite the attempted kidnapping case against the Hospital."
The Hospital's policy is squat in a court of law.