This received a lot of publicity way back when and has gone down in rock history as one of the most self-indulgent demands during a period of perhaps the most self-indulgence ever in the business, but I believe that this demand was strategically placed with a special purpose in mind.
If the band would get to the dressing room and see that their M&M's still had the brown ones left in, they could be pretty sure that their rider wasn't read that closely by the promoter and it was a sign to look for other places where the promoter cut corners. Brilliant!
Concert riders have tamed down a lot in these days of corporate, ultra-professional touring. Lady Gaga's rider, for instance, calls for "a roast chicken, a plate of cheese on ice with a tray of assorted meats, low-fat milk, salsa dips and whole-wheat bread and crackers." Not exactly party material.
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