Not been to Greece for a long time but have seen must places only accept cash, apart from big supermarkets and the like which happily take cards.
5 excursions booked and paid for, online food shop booked and paid for, so this is for drinks, lunch, ice creams, petrol, parking and a couple of dinners out. Family of 5 will have debit and credit cards on us so access to more money if needed.