Because, quite obviously, the state is not going to pay thousands of dollars per account per year to audit child support expenditures and has no interest in having quarrelsome NCP's quibble over every expense.
If you and your lawyer believe that the court will impute a significant income, such that your support obligation will be materially reduced, then that's an option. Often the reduction due to the custodial parent's increased income will be a lot less than you anticipate.Quoting RandallM
Jobs give you a couple of months to raise a child? Do they give workers super growth pills for their children, that compress eighteen years down to a three month time period?Quoting RandallM
If you did not resolve the issue of deductions in your divorce, you follow IRS rules as to who gets the deduction. You follow them either way, actually, filing Form 8832 as necessary, but you have recourse through the divorce court if the divorce judgment isn't followed.
You want them to dip into a new spouse's wallet instead of yours? It's not the new spouse's child. You need to support your own child.Quoting RandallM

