Madballkid 

Bear in mind, this video is not a statement against McDonald's. Obviously, they have to coat their cups with a thin plastic film otherwise the drink would soak through in minutes if not seconds. Not only McDonald's, but almost all paper cup has a plastic film in them. It's about the proportions, and most part of the cup is made of paper, which is an environmentally friendly material.
McDonald's pays close attention to the climate, and they work hard to build a more sustainable food industry, which includes lowering the emission of greenhouse gases, developing and using sustainable packaging and dealing with its recycling, lowering the agriculture's impact on the planet, conserving our forests, and making one of their top priorities to use the planet's water resources responsibly. If anything, McDonald's should be the role model of many other restaurants.