Quote from Niles in You Scratch My Book...
Niles: Anyway, tickets are only ten dollars. It all goes to support Maris' little opera group. Frasier: Dear God, what's the grand prize this year? Niles: Their lead soprano, Mrs. Fitzgibbons, will come to your home and perform "The Ride of the Valkyries". We've sold eight hundred tickets, so the risk is pretty minimal.