The American Express Lounge used to be a good place to wait before a show at the amphitheatre. At last night's Foo Fighters show, before the opening act, all of the tables were reserved, which never used to be the case. I was told that Live Nation season's ticket holders and other Live Nation priority ticket holders get first access to the lounge. In between the opening act and the Foo Fighters, there was a line-up with a long wait for American Express Card holders, while Live Nation special ticket holders got to jump the line, making the wait longer.
I'll take this opportunity to also comment that as fun as the atmosphere may be on the lawn, there are lots of parts of the lawn where support beams obstruct the stage view, and they didn't have the opening act on the big screens. Essentially going to the lawn is watching the big screens as the lawn is so far away from the stage.