The size of the meal not the size of the deal

Today I was on the run and I stopped for lunch at a Subway. I ordered a 6" sub. The young man behind the counter asked me over and over if I wanted to get a 12" for 15 cents more.

He just could not understand that I was not interested.  I finally explained. I know it is a great deal but it's about the size of the meal.  I don't want more food!!! 

I have lost 40 lbs on Isagenix and portion control is huge.  

So I understand it is a great monetary value but  I don't want more food.