Make take out containers into an experience
At the end of the day, going out to eat is a form of entertainment. Restaurants may as well embrace this and turn even the most mundane tasks, like boxing up left overs, into novel experiences. Most restaurants just bring a box to the table for you to fill yourself, but a few turn this into a performance. Not only will they wrap up your food, but they'll sculpt an animal of your choosing from the aluminum foil.
As a patron seeing other tables ask for dragons and dolphins, you can't help but ask for something special too when it's time to go. But, to do that you need to have leftovers, which means you likely to over-order, which leads to more revenue for the restaurant. If given the chance, think of ways to turn every customer experience into entertainment.