I'm with avro707. A couple of weeks ago I was asked to go to a wedding party in a bar/restaurant and do whatever I thought was interesting. I wasn't hired -- it was a favor kind of thing.
I never took the 70-200 f/2.8 off. I could reach across the room and grab headshots, grab a couple of people talking to each other, and on and on.
It was the perfect lens for that day, and I stayed at 2.8 a lot because I didn't want to use flash. True, it was on an FX body (D800). If you're shooting with a crop sensor, then maybe it would be a little long for you.