Why do people from big cities think there is no racism there?
I’m not sure what you mean exactly, but here’s my own view anyway. In a ‘big city’ people tend to meet and work with others from a range of different ethnic groups and think they get on; indeed racism may (should) be directly forbidden in the workplace and there are clear and severe penalties for that sort of behaviour, so ‘there’s no racism’, they think. But what the majority ethnic group (usually, but not exclusively, white) don’t sometimes see or feel are the attitudes of their groups at other times; they think they are not racist, so don’t see that some of their behaviours are very much so. This may be why some people in big cities think there is no racism.