Some time ago, I asked Dr. Vincente Navarro (JHU, Bloomberg School of Public Health, served on the health reform panel under Clinton) a similar question, pointing out that it would benefit them materially by shifting some of their health care cost on the taxpayers. He replied that it is not about the cost (which they can usually afford) but about labor control. Discretionary and non-transferable health benefit can be a powerful weapon to keep labor and unions docile.
Wojtek