How does this work?

I go into QFC for 2 items, soda pop and a steak for dinner tonight. I come home having spent $40 dollars. It isn't like I bought the fanciest steak in the joint. Somehow 2 items became 8 items... BUT thanks to a couple of those 8 items, I will have steak and bacon & cheddar mashed potatoes. Mmmm... bacon & cheddar mashed potatoes. :)