BTW: Note that businesses are allowed to charge extra for the use of a credit card. And many do. For example, a car rental company charged me 4.8%, an airline charged me, etc.

An airport shuttle service in Auckland charges a credit card fee if you book online. No fee if you book by telephone, but then you must pay cash. And their 800-number does not work, if you call from a cellphone, so you may pay for the call on top.