Australia's highly concentrated food retail environment is examined in the context of competitive entry in a small city. Based on a conceptual framework that draws on existing literature, food stores’ customers’ share of wallet (SOW) is measured in a survey (n = 379) which brackets the opening of a new supermarket. A number of variables are recorded in the survey that are not available from other data collection methods. The drivers of SOW are determined using a 2-limit Tobit model which incorporates the direct and interactive aspects of the pathways identified in the Conceptual Framework. At one of the stores (Woolworths), the influence of loyalty schemes is found to vary with customers’ perceptions of stores, with implications for enhanced customer targeting by food retail managers. The impact of loyalty programs is found to be mitigated by the entry of a competitor, particularly in the case of price-conscious customers. Senior citizens are found to allocate higher SOW to small rather than large stores, and there are small effects due to the sex of the customer. There are few indications of a bespoke small city model of the drivers of SOW, but a number of interactions are identified for future research.