As Beck moved around the country, his shows seem to be getting more and more hectic/packed. I've read notes about the prior show in Columbus being so full he had to play 2 sets, and a headline/review of tonight's in St. Louis says "Beck draws overflow crowd" and that hundreds were turned away.
The review was particularly negative about the performance saying that Beck "demonstrated all the responsibility of a drunk baby sitter [sic]." Also that it was "an hour's worth of frivolous feedback and bad hardcore."
More specifically, I guess Beck started the show acoustic and alone, before he sang 'Beercan' with just one of his band behind him beatboxing. Then his band joined him on stage (which the review refers to as Cavity Search for some reason).