Will Muschamp has been known to be somewhat displeased with what he deems poor officiating before, and vocal about it. But no matter how many times he gets upset with a ref, the next time is always great. And you can add his Saturday response to a penalty, captured in this Vine by Tori Petry, to the "OVERCOME THE ADVERSITY ON THE FIELD" pantheon: "DO YOU WANT US TO PLAY FLAG?"
If I had to guess, Muschamp's probably reacting to the holding penalty you can see here on Solomon Patton's rescinded touchdown run, because "...hands are INSIDE! WHAT, DO YOU WANT US TO PLAY FLAG?" sounds like a Muschamp reaction to a hold, and because you can see, in the video at that link, that Muschamp definitely laid into a ref.
Additionally, I don't think Jonotthan Harrison intended to terrify Petry on this jog back to the sideline from Saturday's game; he probably just wanted to do a goofy thing on camera. But he definitely did both.