Adolph Coors, Freddie Heineken, August Busch III and a senior executive from Guinness emerged from a long meeting.
Someone proposed a drink.
Coors said: "I'll have a Coors Light." Heineken said: "I'll have a bottle of Heineken." Busch said: "I'll have a pint of Bud." The man from Guinness said: "I'll have a Diet Coke."
"What," the others chorused, "is with the Diet Coke?" The man from Guinness said: "If you're not drinking beer, I'm not drinking beer."