This article is based on the AskReddit question "People who have visited the US, what is your 'WTF America' story?"
Source can be found at the end of the article.
1/22. I'm Canadian and I went down to the US to do a little shopping. I accidentally pulled out some Canadian bills and the cashier asked why I kept Monopoly money in my wallet.
2/22. I asked an old lady if it's true all Americans carry guns. She smiled and pulled a revolver out of her purse. She was a nice lady.
3/22. I went to Applebees, and was served by a nice young lady called Brittany who asked me with a serious face if we have trees in Scotland.
4/22. Well. I hadn't even arrived yet in the US but in the plane as a foreigner you have to fill a paper to enter the country with various questions among which "Did you come to murder the President of the United States?”
5/22. When I went to the U.S. the first time and ordered a meal from Burger King, ordering a large fry, coke, and a Whopper, I was blown away by the size of it all. Each item was larger than the same item back home, I was already like "wtf", but then the cashier said I could have a second Whopper for 1$! Again, I was like "wtf, sign me up!"
Another time, while I was in Daytona, I went to a restaurant and the woman kept refilling my drink, again and again. Being a bit shy, I did not tell her to stop, and expected a bill with 15$ for sodas, but then I found out the refills were free, wtf!? FREE REFILLS?! I'd only seen that at places like Subway, but so many restaurants in the U.S. had free refills.
I love the U.S. for restaurants and food in general, the portions are massive and very reasonably priced.