"King of Beers" joke

After the Great Britain Beer Festival, in London, all the brewery
presidents decided to go out for a beer.
The guy from Corona sits down and says "Hey Senior, I would like the
world's best beer, a Corona." The bartender dusts off a bottle from the
shelf and gives it to him.
The guy from Budweiser says "I'd like the best beer in the world, give
me 'The King Of Beers', a Budweiser." The bartender gives him one.
The guy from Coors says "I'd like the only beer made with Rocky Mountain
spring water, give me a Coors." He gets it.
The guy from Guinness sits down and says "Give me a Coke." The bartender
is a little taken aback, but gives him what he ordered.
The other brewery presidents look over at him and ask "Why aren't you
drinking a Guinness?" and the Guinness president replies "Well, if you
guys aren't drinking beer, neither will I."