I went to see the Stones on Friday the 13th and I've got the ticket scans to prove it:
There were four ticket price ranges: $60, $99, $160, and $450. We paid $160 balcony seats and Dr. Jeebus and I ended up getting there way earlier than we planned. So we're sitting in our seats when suddenly a Garden employee comes up to us and asks us if we're alone. At first I was afraid he try and molest us or something, but instead we a got a free ticket upgrade to $450 seats there were within throwing distance of the stage. I have no idea why these seats were still available, but it was fucking awesome. And the Stones put on an amazing show too. They may be a trillion years old, but they're still one of the best live bands out there.