Re: Let's take the gender out of this
She's not thinking "Wayhey, cheap food", its about optimising a bunch of shitty outcomes.
But you started out saying:
She will go in to the pizza place first, get a great deal on the pie we want and once they bring it the free garlic bread for while we wait, she messages me to come on in :)
Why do you wait outside until she has got free garlic bread if both of you were not thinking "Wayhey, cheap food" ?