You seemed a little more unhappy about it in you first post. And in my mind you still did the right thing. I saw no issue with what they were doing based on what I understood from your first post. But again, if they have been told not to be there, then they were 100% in the wrong.
I didn't intend to come off that way, but I guess it I did. I have a very tight window Sundays for mapping, the cafeteria opens at eleven and I'm given to 10 am to complete the mapping that is done over the active campus. I also want to do the mapping in the best possible light and that means no earlier than 9 am.
As I said, I know nothing about the RC world other than I wouldn't want to be attempting mapping while they were flying.