What is the importance of the supply closet at the McQuiddy home in the nonfiction book, Invisible Child?

Soon after Dasani arrives at the McQuiddy home with Chanel and Avianna, Tabitha McQuiddy shows them the supply closet. Here, Dasani can select all the personal care products she could ever need. It is full of "Nivea cream, ACT mouthwash, and Prell shampoo" (255). Chanel indicates that Dasani needs Secret deodorant only, and Tabitha shows them all that it is right there. Avianna notices that there is a clear box filled with what looks like money in the supply closet. Tabitha McQuiddy explains that the girls use paper money to buy their supplies so that they get a good sense of how to budget their money. The supply closet is one of the first places Dasani's family sees, and it exemplifies the sense of plenty that permeates the campus of the Hershey School.