Via Chris Foley's blog:
This is rather amusing, even if the song is so painfully bad that the so-bad-it's-funny dynamic doesn't quite work. What's ironic to me is that, although the idea is to show what it would be like for a musical production number to break out in a real-life situation, the real audience for this is not the poor folks stuck in the food-court but, rather, the YouTube audience. The unsuspecting diners become part of the show, as evidenced by the amount of work that was put into hiding videocameras and documenting the surprised reactions. It's basically Candid Camera, which of course is intended primarily to amuse TV viewers, not the people being pranked. The music isn't really designed to communicate with those who are there, as evidenced by the general low-energy bewilderment. Since neither TV nor YouTube can be considered real-life situations, this musical turns out to be just as un-real as all the rest - and a good thing, too. If real musicals like this were breaking out everywhere, I'd never go out.