Perhaps Valkeryguy's rotors weren't junk at all. They may have been perfectly fine and he was only having them turned so that he could install his new rotex pads. Its my understanding that rotors should be turned or replaced whenever new pads are installed.

Certainly, you can install new pads without having a fresh rotor surface and your brakes would work. But, your braking performance might suffer until the pad was worn to match the imperfections of a used rotor. Also, your brakes could be noisier than those installed with a fresh rotor surface.