I heard strange rider requests were to ensure that the venue thoroughly read the contract. If the jelly beans aren't all black, then it's possible that the stage requirements may not be to the performer's liking or even dangerous.
My brother got married in my parents backyard. He had a diverse assortment of people attending the wedding. There was a group of Sikhs that were their in their finery - long flowing tunics and billowy pants and turbans. My son, who was three, saw them as we came around to the back of the house and yelled out loud: "Look, Mommy! Genies!!!"