Originally Posted by flyatlanta

If your girlfriend really loves you, she already knows and appreciates that that you are "playing this silly game." She would expect that you factored mileage-earning into such a significant purchase. In fact, how could she believe that you truly made the best purchase possible if you did not even factor these miles.

Plus, this precedent sets you up nicely to insist on a wedding reception at a hotel where you can earn points for everyone's dinner (though most hotel programs do not allow point accrual for catering events).