Square, stripe, paypal, venmo or any other merchant service, there is a fee range from 2% to 5%. No mater your profit margin is low or high, this fee become significant in the long run of you business. Using KwickPOS cash discount program, this loss/cost can be recovered back from your customer. This picture says it all. Cash price in black, Card price in red.
Restaurant point of sales system, include cafe, bar, fast service and full service, also beauty salon.