Dornier wine estate double charging

My sister and a group of friends went to Dornier wine estate for wine tasting. They ordered 5 cheese platters but when it came to paying the group were charged for 10 platters, they were told that each platter had double the cheese on it. This was a group of students who had budgeted for 5 platters not 10. This is not right, the estate should not have charged them for 10 platter, this ruined their experience and left my sister devastated as she was the one who invited her friends to the wine tasting. It is terrible that Dornier took advantage of these students.