We the citizens pay 100% of all salary and benefits earned by public employees.   However that total compensation picture currently has government workers earning 87 to 93 cents on the dollar compared to what they could be paid working elsewhere.   When you leave off Retirement those employees are getting paid 30+% less than their private sector counterparts.   The only reason total compensation is even as close as 87-93% is that retirement.    

If you plan on arguing for reductions in retirement you better be prepared to raise wages to market values for total compensation.   Good luck with that.