The biggest beer producers in the world meet for a conference, and at the end of the day, the presidents of all the beer companies decide to have a drink together at a bar.
The president of Budweiser naturally orders a Bud, the president of Miller orders a Miller, Adolph Coors orders a Coors, and so on down the list.
Then the bartender asks Arthur Guinness what he wants to drink, and to everybody's amazement, he orders tea!
"Why don't you order a Guinness?" his colleagues ask suspiciously, wondering if they've stumbled on an embarrassing secret.
"Naaaah," replies Guinness. "If you guys aren't going to drink beer, then neither will I."