The rapid growth of the e-commerce market in the retail sector has led to a greater demand for home delivery services in recent years. In order to develop policies to address the issues related to delivery demand, it is critical to understand the demand mechanism of online shopping. Furthermore, the relationship between proximity to mass rapid transit and shopping mode choice mechanisms has not been studied, although, in the field of urban design, accessibility to mass rapid transit is known to affect travel behaviors. We focus on the relationship between proximity to mass rapid transit stations and the shopping mode choice mechanism and estimate structural equation models, considering in-person and online shopping propensities as the latent variables. We use the two datasets. One is from a web-based survey of online shoppers in Japan. The other is the 2019 NYC Citywide Mobility Survey data. The results based on Japanese survey data indicate a clear difference in shopping mode choice mechanisms between MRT-dependent neighborhoods and non-MRT-dependent neighborhoods, while such a difference is limited in NYC. Furthermore, the study reveals how individual and household characteristics and accessibility indicators affect online shopping propensity based on the type of neighborhood and city/country.