Children as Passive Income, by the numbers
In 2021, the child support program collected $32.7 billion, according to data from the Department of Health and Human Services (HHS) (https://usafacts.org/articles/how-much-child-support-do-parents-actually-receive/)
The US federal government gives $4 billion annually to the states to enforce child support collection. (Erasing Family (2020) | Parental Alienation documentary, | US Divorce Court System)
State Bar Associations spend hundreds of thousands fighting shared parenting bills. Family Law & Divorce Lawyers & Attorneys bring in $11.2 billion a year.
Child custody evaluators make between $40,920 and $116,960 (https://www.comparably.com/salaries/salaries-for-child-custody-evaluator).
The child support industry alone is $50 billion. A significant portion of that never reaches the custodial parent, let alone the children but instead funds state coffers.
This does not include many jobs generated by fighting custody battles in court, rather than working it out amicably with a 50/50 shared parenting default.