In one embodiment, a customer authentication system includes at least one sensor configured to provide location information of people around a product display section. A customer authentication device is configured to provide customer identification information. A processing device is configured to perform location tracking of the people around the product display section based on the location information from the one or more sensors. The number of people in a predetermined area around the first customer authentication device is then determined based on the location tracking. The processing device enables customer authentication via the customer authentication device if only one person is in the predetermined area and disables customer authentication via the customer authentication device if more than one person is present in the predetermined area.