Section 21 cheerleaders and stadium etiquette

At the State game I was mostly surrounded by Spartans.  A few of them were very annoying, but the fans that bugged me the most in the immediate area were a couple with Maize 'n Blue gear.  Why?  As far as I could see, they had a poor grasp of stadium etiquette, at least as I understand it.  I'm accustomed to standing up often for big plays as the "standing" wave cascades upward from the field.  No big deal ... I usually enjoy the process and it seems healthier than sitting for the whole game.  But, outside the student section I rarely see people standing continuously.  That's what these two fans, who were apparently boyfriend and girlfriend, were doing.

When it became clear that this was going to be their baseline posture, I decided to engage them in conversation.  (They turned my seat into an obstructed-view location.  It was that simple.)  I had to reach over a row to do so and the woman was closest, so I started with her.  When I asked whether she wouldn't mind sitting for "less important plays" she gave me a really nonlinear answer along the lines of "GO BLUE DEFENSE AHHHHHHH!!!"  Ever accidentally step on a cat's tail?  Remember the sound the cat made?  Multiply that by six or seven and you'll have some idea of how the chick sounded.  It hurt my ears.

It was my brother-in-law's turn, so he tried poking the guy, who went ape$hit.  In spectacularly nonlinear fashion, he started screaming to everyone in the area about how Michigan hadn't beaten State in many hundreds of days and how we needed to STAND UP and support the team.  The doofus was the self-appointed spirit bunny of Section 21.  Even the meathead Spartans behind me were stunned at the outburst.

Anyway, I'll spare the readers the rest of the details.  They settled down a bit and, shortly after the dude screamed himself hoarse in the third quarter, they left (!).  So much for the cheerleader role ...

Were they justified in standing up in a sea of sitting people?  Spirit aside, I just wanted to see the game.  I honestly didn't understand why they couldn't sit like everyone else (since their own view would not have been obstructed).  What do MgoBloggers think of this?