In the good old days of high-end audio a scant dozen years ago, equipment was powered with stock, nothing-special power cords. In fact, much audio equipment had captive power cords — attached, that is — so even if you wanted to use some other cord, you were out of luck.
Thus, an exploitable niche existed, and the after-market power cord came into existence. Now just about every cable manufacturer has a power cord or two in its line, and companies like ESP and Shunyata Research sell only power products, and chiefly power cords.
~ Marc Mickelson, Editor-in-Chief of the SoundStage! Network