I was not aware of an SEC - Big Ten "rivalry" until recently
(Detroit, Michigan, USA)
As a lifelong Michigan "Wolvereens" (good job with the spelling on that one, by the way) fan, I can honestly say I was not aware there was apparently a rivalry between these conferences until recently.
Much of this probably has to do with the fact that Big Ten schools have traditionally considered the Pac-10 to be its rival conference (if any at all), and at the same time, most Big Ten schools have no conference allegience whatsoever.
No fan of a school affiliated with the Big Ten thinks to himself following any game between schools of the two conferences, "Well, that just proves the Big Ten is better than the SEC."
Frankly, the lot of us are happier to see other members of our conference tank, because we simply do not like each other and see no reason to share some sort of false comraderie based on geographic association. Perhaps that's where we differ.
No person (Big Ten fans included) ever says, "The Big Ten conference is superior to the SEC." We generally mind our own business.
But, at the same time, it gets to be a little annoying when we get to hear "The SEC is the best conference in the country" unprovoked week in and week out, especially when we're not sure we believe that.