Does this break graduation protocol?

While I see your point, these people are older than you (I ume) AND are much farther up the career ladder than you are so far. These people helped all the students graduate! Give them some credit. It would be kind of mean to say "sorry, but you, you, and you aren't allowed to sit on stage. you must sit below the people who are barely out of school while your colleagues are up there sitting on stage."