Why Van Halen had brown M&Ms contractually removed
Nowadays, something like this can also be seen as somewhat insulting to a venue.  We spend hours pouring over contract riders to make sure we meet the specifications, and many more hours pricing out the materials and labor necessary for an event.  If the lead singer of the band is putting M&M clauses into riders, instead of the touring production manager dealing with the venue TD directly, there's already something wrong with the negotiations.