Heathcliff thinks that he has gotten an awesome pizza, because the sign on the door says "NEW." The pizzeria people that Heathcliff out earns by being a fat fucking cat think that they've done an awesome job of getting rid of old pepperoni. If it only took one pizza to clear up the old pepperoni, they probably didn't have a need for "NEW" toppings, but then there wouldn't be a joke. Couldn't go without the jokes.