Definition of "fosters"(Australia-made beer) from urbandictionary

[facecatwt]

the content was like these below:
Fosters
What the yanks reckon Aussies drink, also what they think we call beer. We have a totally different word for that though.. We call it... wait for it... "beer".
Fosters sucks, you'll be hard stretched finding a fosters in any real watering hole.
If you want fosters in Australia, go to some yuppie terrorist(tourist) bar in a CBD.

Question:
Who are yanks?
It says they've got a different word for that and why does it say they call it beer again?
What the 'wait for it' here mean?
What does hard stretched mean? real watering hole?
What's yuppie terroris(tourist) bar?

 

[SoothingDave]

You have never heard of the word "Yankee"? "Yanks" is a shortened form.

Fosters is advertised in the US as being "Australian for 'beer.'" This "definition" is obviously from an Australian, who is telling you that Australians call "beer" "beer."

And that they do not consider Fosters to be representative of actual Australian culture, but is only for tourists who think it is authentically "Australian" (because of the beer commercials they have seen back home in the US.)

 

[JMurray]

not a teacher

I agree with soothingdave.

Regarding your other questions:
"wait for it" – he is jokingly pretending that he is about to say something surprising. The point being that what follows is actually very obvious.
"you'll be hard stretched" = you'll have much difficulty
"watering hole" = an informal term for a bar or hotel where the public can buy a drink. The use of "real" suggests the writer means a genuinely Australian bar rather than one designed for tourists.
"terrorist (tourist)" – in some accents the two words can sound very similar. The writer expresses his dislike for tourists by using this similarity.