To provide some context, this question occurred to me while I was considering the cement retail market. If one considers retailers selling cement of only one brand, then the concept of brand loyalty is useless as there is only one brand. In order to understand the behaviour of consumers, one must consider store-loyalty (An idea first introduced by Ross Cunnigham in 1969). If the retailers are trying their best to maintain store loyalty then what can be said about the kind of competition they are engaging in, given that there is a large number of retailers?
I think that the competition should be monopolistic in nature, as retailers, like shopkeepers, are trying their best to attract consumers. But the only difference lies in the fact that consumers make repetitive purchases at shops whereas a majority of the consumers going to a cement retailer make a one-time purchase(Mainly for the construction of houses). Also, the target of the shopkeeper is to not only increase his sales but also to maintain consumer loyalty, whereas the cement retailer cannot aim for the second option due to the aforementioned reason but yes he would too, want to increase his sales by expanding his consumer base.