Some buffets will allow you to do a “take out”; instead of sitting inside and eating “all you can eat”, each patron is given a styrofoam container to do take out.
That makes sense— explains why they are handing out big styrofoam containers. Surprises me that a restaurant would do that, though— still, I guess it helps to move the food, even if the profit margin goes down. You’d have to really love Chinese food to eat leftovers as a family for “several days” though! That’s a lot of moo shu pork!!!