Read the following article and answer the question.

It seems like most of them live in high - rise apartments that are like small forests of steel and concrete . Cha 's apartment complex has about ten high - rises around a small park with a half - court basketball area and exercise machines that utilize the user 's weight as resistance . There are little reminders that I ' m not in Kansas anymore . I realized that after walking around Seoul and being driven through miles of it that I never saw a bit of graffiti .

What may be the reason for there being no graffiti ?
They live in a nice neighborhood .