Brewery managers go to a bar

In Münchens Oktoberfest, there was a meeting with international brewery managers. After the meeting they decided to go to have a drink at a local Bierstube, well known for their international selection of beers. Coronas head manager sat first on the bar and said:
- Por favor, Senor, could i have a bottle of Corona, the best beer in the world.
The bartender got a bottle, opened it and poured it to a glass.
Next up was Budweisers head manager, who ordered:
- A can of the king of American beers, Budweiser, Thank you.
The bartender gave him a can and a glass.
Then it was Guinness' head managers turn. He ordered:
- Could i get a large coke with ice, please.
The bartender gave him the coke while the two other brewery managers watched stunned. They had to ask:
- Why didn't you order Guinness?
The Guinness' head manager answered:
- I thought that if you fellows don't want to drink beer, I won't drink it either.