Kümmerbünd is a relatively unknown musical group, which has agreed to play a concert at Club Now, a popular music venue, for a flat fee of $2.500. After the contract is signed, but several weeks before the performance, Kümmerbünd is suddenly catapulted to fame with the success of a new single, “Smell the Glove,” a cover version of an old Spinal Tap song. Kümmerbünd now has many offers to perform at much higher prices. Kümmerbünd calls Club Now and says that it will not perform unless the payment is increased to $10,000. Club Now at first tries to insist on the original deal, but finally gives up and agrees to pay $10,000. 

 On the night of the concert, Club Now triples the cover-charge and sells out every seat, clearing $25,000 in profit. When Kümmerbünd asks for payment, Club Now gives them a check for $2,500. Kümmerbünd demands the remainder. Club Now refuses, saying, “We had a deal.” Kümmerbünd sues. Should the band be able to receive the extra $7,500 in compensation? Why or why not?