A theme in the book would be showing the snotty nature of a group of people in a place. Ackley is a person who never brushes his teeth or looks presentable. He is constantly covered in acne and his clothes are a mess. He looks like a homeless man. But he has clean fingernails. They are always trimmed to perfection, there is never any dirt under them and his hands are always washed. So that could show that first impressions are there for him to do something. The fact that his hands (look) are clean just have an persona of a fake outer layer.