The Guardian article seems to be a bit light on details. It seems they were asked to remove the food or leave and get a refund but refused before getting into a "heated exchange" with staff, then the police were called. Apparently the brought in "a lot of outside food", “Beverages, snacks, hot food, you name it.”

I haven't been to the cinemas for a long time, sneaking in lollies and stuff was a given, but I think it's understandable not to bring in hot foods and meals. Considering they've always had rules about no outside food, getting caught means either getting rid of your food or leaving. I wouldn't verbally abuse staff if I'm the one breaking their rules.

The Herald article has a lot more detail: https://www.nzherald.co.nz/entertainment/food-brought-into-pukekohe-movie-theatre-women-trespassed-police-called-after-heated-exchange/YPZA3KB3ZBCPVPLYMXIIACUBMQ/