I think that the child support laws are all wrong. The law is based on the premise that fathers should spend 50% or so of their after-tax income to support their kids. Most men are indeed willing to work like dogs to support their families, as long as there really is a family unit to support. They are not willing to pay money for the purpose of destroying the family.
When combined with no-fault divorce, child support laws imply that a wife can walk away from a marriage for any reason, and take her husband's income with her.
There is no requirement under the law that child support actually be spent on the children. It is a big, fat, financial incentive for wives to walk out of marriages. The vast majority of divorces are initiated by women, and they are often guided by a selfish desire to take their husband's monetary support, without having to provide any emotional support in return.