Fat Tire is NOT brewed by Miller. No way, no how. Fat Tire is brewed at New Belgium Brewery, employee owned and brewed in Fort Collins, Colorado.
As was pointed out, Blue Moon is an example that most people have no idea is brewed by MillerCoors (and isn't all that bad either...) Another example that upper midwestern folks know is Leinenkugels - used to be a family brewery that is now part of the MillerCoors empire. Some of their popular brews used to state they were proudly brewed in Chippewa Falls, Wisconsin. Now many of them state Proudly brewed in Wisconsin, meaning some production was shifted to Milwaukee.