“…Among the former, e.g., [ 14 , 15 , 16 , 17 ], are studies on consumer attitudes and behavioral causality, e.g., [ 5 , 18 , 19 , 20 ], as well as analyses of HMR markets and marketing strategies, e.g., [ 2 , 7 , 21 ]. Studies of HMRs from a nutritional perspective have mostly focused on the nutritional balance and quality of HMRs, e.g., [ 3 , 22 , 23 ]. Despite HMR-related research achievements in various academic fields, research to understand the characteristics of products is essential in seeking a sustainable service strategy of COVID-19 [ 24 , 25 ].…”