For Russians, a smile in public is not the polite expression that Americans reflexively offer strangers on the street. A smiling person must have a good reason for doing it, and it should be obvious what that reason is. When people smile without hesitation—for no reason—Russians find those grins artificial or insincere. And they think those people have a few screws loose.
the man told him, \"In Russia only two types of people smile: idiots and rich people—and rich people don't walk on the street.\"