Small talk. I'm not much of a small talk person even as an American, but I tried to be polite and chat with a cashier at a market, and he looked baffled and didn't really know how to reply. Americans will chat with anybody and everybody, especially if you're from the South.

When they use burgers per bald eagle instead of km/h.

When they think liberals are the far left.

I am German, and when a woman told me about a sinkhole in their hometown, they said, "I don't know what you measure in, so it was the size of about 2 McDonald's restaurants." that woman is now my Fiancée.

I'm an American that works for an international company. Europeans are often amused by how we describe distances. Instead of saying, "we're x number of miles from that city ", we'll say, "we're two hours away" , or "that's a four hour drive". They're also universally blown away once they realize how big the US is.

Talking to strangers in public. After living in Germany for two months I was horrified when a stranger on the bus commented on my shoes.

HeeseungsAce:

Yup! Went to Florida, and when I went shopping I was wearing a skirt, and a girl maybe a few years older than I was commented on how she loved my skirt. Would NEVER have happened in Denmark, that’s for sure.

Over 90% of NFL players getting chronic traumatic encephalopathy (CTE). The NFL will be viewed like we view gladiatorial battles now.