How does social class affect relationships both in The Kite Runner and reality?

Throughout the novel, Khaled Hosseini depicts how people treat others differently because of their social class. This treatment negatively affects many relationships throughout the novel. For example, Baba refuses to have an open, loving relationship with his son Hassan because Hassan is a Hazara. Amir is also a privileged Pashtun who looks down on Hassan and treats him disrespectfully at times. It is socially acceptable for Amir to treat Hassan with contempt, which causes a rift in their relationship. Amir never fully expresses his true feelings of friendship to Hassan because Hassan is from a lower social class. Both Baba and Amir's relationships with Hassan do not reach their full potential because Hassan is a Hazara and they are Pashtuns.

For centuries, Hazaras living in Afghanistan have suffered persecution at the hands of Pashtuns because of their religious and ethnic differences. Hazaras have prominent Asian features and are Shiite Muslims. Although they compromise 20% of the population, many Hazaras live in the mountainous regions of Afghanistan to avoid persecution. These provinces are extremely underdeveloped, and they do not have the same opportunities for advancement as Pashtuns. Relationships between Pashtuns and Hazaras are also socially discouraged in Afghanistan.