Pitcture this scene:

Its Christmas morning. Two 3yr olds and an 8yr old are still clad in jammies opening what few presents their parents could buy. There is a ring of the doorbell. "It's Santa!" screams one of the wee boys in delight. The door is opened and there stands a jolly red elf bearing two garbage bags full of gift-wrapped presents -- all with only one name on them. Imagine the dissappointment the other 3yr old felt. Now imagine the grief 'Santa' went through.

"If you haven't enough for everyone then don't offer at all."
~ everyone's mother has said this at some time or another

This is part of the manners I was brought up with. Every kid got a valentine from me whether I liked them or not. Once I was too old to have the entire class over for a birthday party, I was under strict instructions not to hand my invites out at school or in front of other kids. It was a matter of practicing common sense.