He'll change his phone number and get his mom to make a minimal payment on the child support arrears. He will not be jailed, or fined, or punished. You've obviously never been single, or a mother, or raised by a single mother. W-2 has done more to devalue society's perception of Motherhood than any program to date. If she stays home and cares for her own, however, she is pegged as irresponsible and subject to social sanction.
Single moms have twice the responsibility and half the help.
Some things just cannot be measured in dollars and cents.