Here is how no fee financing makes sense
The first calculation is to compare the fees of a no cost loan and divide it by the payment savings of a loan with fees. That will give you a break even point in months.

For Example:
$400,000 loan with no fees at 5%
$2147.28 Payment
versus a $404,000 loan with $4000 in fees at 4.75%
$2107.46 Payment
Difference in payment: $39.82
Difference in cost: $4000
Break even point: 100 months
So, it took 100 months to recover the cost of the lower rate loan.
It's the Borrower's Yield Spread Premium Now
With the mortgage broker law changes effective Jan 1, 2010, the yield spread premium that comes from the lender is now owned by the buyer to use in whatever manner they want.
On many transactions, that can be as much as 3% of the loan balance. For a loan of $300,000, that would be $9000 that can be applied to closing cost and pre-paid items. This is a perfect way to minimize the investment needed to buy a home. Although a higher rate is charged for the cash up front from the lender, in many instances it is the most prudent decision.