It is expected to share with family.
John is at his mom's house where he ordered a large pizza and as he's at the door getting the pizza his mom asks him for a slice.
John wants to respond to his mom's request for a slice.
John tells his mom she can have half the pizza, forget a slice, that's why he ordered a large.
John tells his mom that he paid for the pizza and if she wants a slice she can order her own.
John's mom is delighted and is excited to finally get that yummy pizza in her mouth.
John's mom is sad that John won't share his food with her and that he's so selfish.