Why do the Ivies process financial aid long before decisions?

And other colleges that notify late March/Feb 1, like Stanford, Georgetown, etc. Why do they process your financial aid nearly two months before decisions are supposed to be made? Doesn't this add additional administrative burden, especially since most students won't even be admitted? Possibly, do the colleges look at your FAFSA/CSS to determine covert factors of admission (e.g. the order of schools listed on FAFSA tells them how you rank your colleges by preference)? I am probably reading too much into this, but it doesn't make sense to me.