Originally Posted by findark

It might be FT heresy, but I always have to strenuously disagree with characterizing this as "not paying". Rakeback on your credit cards absolutely has cash value and can be received as cash if that's what you prefer to target in your card portfolio. If you tender miles or CC points for a ticket, it's not free or even close to free - you're just paying with a currency other than dollars because you chose to save some money in that currency. Moderately less true for airline miles you accumulated by flying (since you have no flexibility), but there's still the opportunity cost factor.