In terms of ideas on how to make things more "fair", IMHO all attempts at making old situations "fair" result in new situations that are "unfair".
As I am sure most of us have realized, the justice system is not about fairness. That is why it isn't called the Fairness System. The reason society has dictated that child support must be paid, is that it prevents the state (or others) from being financially responsible for your child. That's it! That's why states will NEVER get rid of child support. If they did, the welfare ranks would go up exponentially.
If you think that taxes are bad now, and stop requiring child support, stop enforcing child support.
This is why you go to jail! I guess that's the only stick that makes so many comply with the orders. But it is much more about stopping the food stamp reliance that was mentioned as an viable resort for those caring for children.
So, if you ask me, motivation aside, when a CO enforces child support, one could see it as a attempt to avoid going on welfare and having to rely on state services. Lets call it: motivation for one not caring for children full-time to get a job. And if the NCP has the money to pay, and is just not paying, everyone seems to agree that person should go to jail. In either case, one can at least understand why they end up in jail.
And I absolutely disagree that one should "justify" how child support is spent. Who would judge which of those pennies where justified and which were not? The new wife? The new husband?