When you purchase a ticket to any concert, you run the risk of not getting the experience you paid for. Outdoor shows get rained out. Favorite songs don't get played. Opening bands go over their allotted time. Sometimes a musician is just having a very bad night. The one variable any musician can feasibly control is the length of his or her setlist, but do bands like Interpol even have to give their audience more than an hour of their time?
Brandon Marshall Jenny Lewis can pretty much play as long as she wants, as far as we're concerned.