Exactly why I prefaced the post with it being anecdotal. Although they did not apply entirely to the same schools, the schools that the 3.6 interviewed at were schools that the 3.8 applied to. Both submitted their applications as soon as possible, although the time apart may be a little bit off - it was not, however, weeks or months apart from each other. I don't want to divulge more information to maintain their anonymity. I am sure differences may have arisen within the more subjective aspects of their application, which, once again, makes this case anecdotal.
I still maintain that a GPA and MCAT are the most important parts of the application, like I mentioned earlier. But as a previous poster also mentions, the strength of an undergrad program does play at least somewhat of a factor with most else being equal, such as Harvard, Yale, Hopkins, etc.
There are other schools out there that give less of an emphasis on undergrad institutions. I know WashU is big on just stats, and accepts from a wider range of undergrads than does Harvard. Like I mentioned earlier, it is school dependent.