Poor customer handling at cashier tills

Shoprite should do something about their cashiers, who are allowing customers to hold up queues, whilst waiting for them to do transactions on their phones. Its really inconviniencing and very unfair to other customers. Shop managers seem not to be addresing this issue, although they are well aware of it. The worst branches I have personally had bad experiences in are the shoprite in Sophiatown, and the one in Mayfair. Cashersiers and managers simply dont care.