Dana and Kevin may not feel at home due to the absence of familiar emotional attachments and memories associated with their past, which resonate more with their concept of home than their present surroundings do. The importance of comfort and social bonds in feeling at home is amplified through the example of Andy's homesickness at summer camp.
Dana and Kevin might not feel like they're home because their current environment lacks the nostalgic feeling and memories that they associate with the concept of home. This could be the same as the figure in the text who looked back at the past and felt that it represented their reality and happiness. Their past experiences and the strong emotional attachments they have formed can make the past feel more comforting and familiar than their present situation.
Similarly, the example of Andy being homesick at summer camp hints at the importance of feeling comfortable and accepted in one's surroundings to truly feel at home. The camp, a new environment, lacks the familiar social bonds and emotional security that Andy associates with the idea of home. Until Andy forms new relationships and adapts, he will not feel truly at home in the camp.
In the context of the reading, the home can also represent a place that is intrinsically linked to one's identity and sense of belonging. When one's environment changes significantly due to human activity or other factors, it can lead to a sense of disconnection from what once felt like home.