As someone who divorced with no kids, I must say it would annoy me greatly to show my ex how much I made. This is where I much rather deal with the state than each other.
I honestly thought it a given. I don't doubt that many people hesitated, or lied, but I thought it was required for support reasons. But going through the state sounds like the best path for us.
XH has no clue how much I make, and I thank baby jesus for that. I can assure you if he saw my wages he'd be constantly bitching about how "I" don't need child support.