Mate, sometimes it just isnt safe to allow kids to stay with their parents. As cruel as it is, Ive known babies to be removed at birth for periods of time if the mother's post natal mental health meant she had the potential to kill the child whilst not responsible for her actions - isnt that a good enough reason? And like Ive said before, the public can't and actually shouldn't be given any information around these cases due to confidentiality laws.
And you can bet what you like, this money doesn't go on wages or there'd be a lot more people training to be social workers than there are.