Our Little Cafe Laurieton

I go to the Little cafe regularly. I go with friends and we normally get milkshakes. This last time My friends got their normal milkshakes of a glass plus another half glass in the mixer container. I got just one glass. No container with the rest of the milkshake. The girl said that was what was mixed and thats what you get. I said I should get what the others get for the same money and I should get money back if its not the same. She ignored me and walked away. . Did she think I was stupid because Im old or was it a deliberate insult to me or was it just nastiness or incompetence on somebody's part. In any even its NOT ACCEPTABLE and service like that deserves ZERO custom.