Is Breast Feeding all that cost effective?

"They say" breast feed - it's free. Or cheaper. (Yes I know I know it is "better" for baby too. But if you breast feed your kids- but then have to get a boob job afterwards - is it really "cheaper". I am just saying.

I guess the question is - how many kids do you have to have to make the later needed boob job cost even out and still be less than formula?

All I know is that I am hungry ALL the time. So the food I am eating alone right now can't be much cheaper than formula.

I am just sayin'.