Green Bay has managed their cap situation very well over the last 25 or so years. Ron Wolf started it, Ted Thompson continued it, and Brian Gutekunst and Russ Ball have learned from those fellas.
I have no doubt they will create a cap-friendly deal for Rodgers (i.e., front-end loaded, bonus driven, etc) that will keep them able to operate as they have been since Wolf came.
It helps when you don't have a GM leaping blindly into free agency each year....and what's really amazing is that drafting in a disadvantageous position hasn't hindered them from being in playoff (and Super Bowl) contention almost every year.
I understand that lots of fans look down their noses at the Packers, but you really can't argue with the results.