Once the government specifies how the screening is to be done, what real difference does it make to travelers what uniform the screeners wear? Deregulation would make a difference, but a regulated service provided privately is very similar to a government provided service. Just look at the US Postal Service.
That is why the government should be kicked out of airports and security should be returned to the airlines and the airports.
The government should not be permitted to dictate airport and airline security regulations. They've proven too often that they are incompetent, un-American morons.