Beer

Three leaders of the big beer companies meet for a drink. The president of XXXX orders a XXXX. Hahn's president orders a Hahn and the president of Tooheys orders a Tooheys. When it is Guinness turn to order he orders a soft drink.
"Why didn't you order a Guinness?" everyone asks.
"Nah," Guinness replies, "If you guys aren't having a beer neither will I."