what the hell is it with dr dos

I've had about 6 threads lately with people trying to install XP and encountering dr dos is microsoft using this dos alternative on their XP disks or is there a warez copy out there using it as a boot system ? most of these drives have been formated prior to install and are still getting a dr dos prompt on boot this is a uncomon program and all of a sudden seems to be everyware can anyone shed any light on this ?