But nowhere in the book do they say that the employer WILL give the employee all the money that the employer was paying in taxes. In fact, they specifically discuss the payroll tax and talk about how this money is actually a labor cost that the employer calculates when determining how much to pay someone, but that it will be up to the employer to determine whether or not to give this money to the employee after the implementation of the Fair Tax. Their calculations are based on the employer NOT giving this money to the employee, as far as I can understand.
But, it's currently money that the employee doesn't see anyway, except in the form of retirement benefits. However, under the Fair Tax plan, those retirement benefits will continue to be funded at the current rate, so, in effect, the employee will be seeing the benefit of having that extra money paid to the government for them, even though it won't be coming from their employer directly.
The net effect to the employee is that they'll get 100% of the check that they've usually seen FICA, Social Security, and Medicare taxes taken out of. If there are employers who feel they can stay competitive and also feel that their employees deserve to receive that extra percentage, then good for them, and I'm sure potential employees will be climbing all over themselves to work for those employers.
see page 111