Smiling at strangers
Though this can vary a bit by region—we’re looking at you, New Yorkers—in general, Americans are much quicker than the average foreigner to smile at a stranger and offer a warm hello, even if they’re just passing each other on the sidewalk. These kind greetings can catch foreigners by surprise, and usually it takes a few “hellos” before they trust that it’s not some kind of scam.