Inviting the kid sitting alone costs you one chair. It might change their whole year.

Almost all of the cost here sits on one side. Sliding over is nothing to you and forgotten by dinner, while on the other side it can be the difference between a year somebody describes as fine and one they describe as lonely. They might say no, and that is fine too. You will probably never find out which it was.

Do the concrete version rather than the warm feeling. Say the actual sentence, move the actual bag, ask a real question and then listen to the answer.