Personalisation
Know the name of all your customers and treat them the way they deserve it. Make them feel welcome and important which are the two most important factors determining good customer service.
Customer focus
Know the past orders and start preparing them instantly. People are habit creatures and will order the same things in more than 90% of all times. Rather than asking the same questions over and over again, spend some time to get to know your customers better.

Take control
Know what your customers order and make sure to stock the items your customers recurrently want. In high competitive environments you can't afford to run out of your profit generating products.
Analysis
Analyse the orders of your customers. Get the insights for up-selling, cross-selling, and discounting opportunities.
Time
Save time in the ordering and check-out process and be able to serve more customers in a shorter amount of time without loosing the intimacy of a good customer relationship.