Agreed. I wish everyone would just standardise on "Mac" and "Windows" rather than the frustratingly ambiguous "PC" (which half the time means both and the other half means just Windows...)
It's just that traditionally some games were never released for the PC
LOOKING AT YOU MICROSOFT; HALO. When it states PC, it's just very clear that it is intended to be played with a keyboard and mouse as input devices.
Personally I would never be interested in a console only title for the controls handicap I'd using a controller. Controls are for platformers only.