When does it get to be too much?
Just needing gas - I can get .10 off per gallon if I buy a $25 gift card at Kroger (4x points this week!). Obviously, I'll use my new AA card to get to the minimum spend to get the 60k frequent flyer points. Or maybe my Freedom card to get 5% back since I know my health care premium will hit the minimum spend in < 3 months...
Oh, wait, checking the gas prices online, the Shell station close to the Kroger has gone up, so it's probably not worth going out of the way. I'll go to the Shell station nearest me that's cheaper. When I get there, surprise, it's gone up, too, but if I use my Shell gift card, it's .05 off anyway. The gas card was bought at Harris Teeter - you get a $50 Shell gas card for $40 when you buy $50 worth of food, but I had to buy $60 because I had a $10 off coupon for food, which took it down to the required $50. And then I used the Freedom card to get 5% off both the groceries and the gas card.
Confused yet?