By definition, if you go back in time and change an event ( the smallest event ), an alternate reality is created because the people in the future from where the time traveler came from ( or his message in this case) does simply vanish. Ergo, the original reality has to exist. Same thing happened when Biff stole the Almanac...

Also I miss MK2/MKSM Kintaro, I hat the cat he has become.