Don't know if you've ever set up an event that involves the appearance of a major celebrity. I have, and, over the years, I've done it many times. Each event is different but each requires big league security and coordination within the venue of all employees and all elements involved, including media participation. Sometimes local police have to be hired as guards. All aspects of the event have to be carefully coordinated for the safety of the celeb and the success of the event.
Recently, Sarah Palin did a book signing at a WalMart in Iowa. CNN thought it would be a hoot if their crew (with reporter Jim Acostas) jumped the line to ask her a few questions.
I'm not sure what there is in the air that they breathe that makes it okay for CNN reporters to do this sort of social abrogation, or what it is that makes their anchors think it's funny. There was security in place and the CNN team just waded into a herd of WalMart customers. If they had pressed forward without acknowledgement, someone might have been hurt.
As it was, they were moved off-site with some "encouragement."