The State of Alaska also can take drivers' licenses and other professional licenses, but rarely does it. The standards of due process they have to meet, the many levels of appeal the obligor has available, etc, make this a very slow and inefficient system.
Meanwhile many of the children are on public assistance and the $$$$ due is in fact due to the government (taxpayers) for repayment.
I do like the passport denial law, but have never seen it put into action in real life - glad to hear it is working somewhere.