Capturing people's behavior patterns, such as purchase patterns or shop-around-behavior patterns, are big marketing concern since such patterns are good resources to invent new marketing services. To this end, a lot of studies using POS (Points Of Sales) data have been conducted to extract purchase behaviors for CRM (Customer Relation Management). In addition, since a lot of widespread sensor devices, smart cards or mobile phones have become available recently, anyone can try to analyze pedestrians' trajectories obtained from GPS data and extract people's behavior patterns. However, only few research has been conducted to analyze relationships between boarding and purchase behaviors based on usage histories of smart IC cards. This paper presents case studies of purchase behavior analysis based on usage histories of smart IC cards, especially focusing on purchase behaviors of passengers who just get off trains.