[Tax-chick]

and people actually got up and left.

Maybe they were done their coffee and wanted to get on with their shopping or go home. Performing for a casual audience, rather than one that purposely came to hear the music, means that some people are going to move on.

[Joe 6-pack]

"Maybe they were done their coffee and wanted to get on with their shopping or go home."

Maybe they're just really bad singers(?)