Can you cite a source for that? Googling it only comes up with this particular comment.
An attempt at a definition: "you can't eat fish and chicken unless you grab them with your hand, and you should also use your hands on (your) woman". It is a play with the phrase "βάζω χέρι", which means to grope, to feel up. Not very politically correct, I know :)"
An older person told me that a lot of years ago when I was a child and was trying to eat a chicken thigh with fork and knife. Only understood the chicken part back then...
Of course that excludes all the things they eat on bread.