From Kris Shaw, a TA in for my ECON 101 class, I learnt that the band Van Halen once required that brown M&M’s not darken their dressing room door. Why? Maybe it was a lark. Perhaps, a member of the band (or two) could not resist chuckling over the idea of a minor factotum appointed to the task of sorting the M&Ms. When minor factotum is asked what they did that day, the response was bound to elicit guffaws. However, minor factotum might have made it a point to not wash their hands before sorting the M&Ms. Then, who would be laughing harder?

A copy of the M&M rider can be found here. Along with van Halen’s explanation of why the rider was included:

……the group has said the M&M provision was included to make sure that promoters had actually read its lengthy rider. If brown M&M’s were in the backstage candy bowl, Van Halen surmised that more important aspects of a performance–lighting, staging, security, ticketing–may have been botched by an inattentive promoter.

So the rider helps screen, apparently, whether the promotor pays attention to detail. I think the explanation problematic. It suggests that it is hard to monitor effort expended by promoter on important things like staging for example. So, monitor something completely irrelevant. The strategic promoter should shirk on the staging and expend effort on the M&Ms.