It is a silly comparison because it doesn’t compare salaries for similar levels of skill and work.
The government has reached a point where most of the very low paid, low skill work is hired out to private contractors. They don’t hire people to empty the trash cans and sweep the floors, they hire the private sector for that.
Thank you ...
It is well known that those government employees that work for the defense department (mathematicians, engineers, etc.) could make more money as a contractor ... hands down. But those who choose govt work often do it for the work ... there is more opportunity to engage in basic research where the point is to progress the science, than in the private sector where the main focus is to take that good science and turn it into a product to sell.