How to fix "Puppy Potty Spots" in your yard - getting it green again

I'm not sure this is cheaper than grass seed  and it may just make a good experiment but here goes....

From lifehacker

How to make the grass green again


Dilemma: You got a new puppy, and now your once beautifully green lawn has bare brown patches all over it from dog pee.

Solution: Pour some beer on the problem areas, making sure the foam's covering all the naked spots. The grass will be greener in no time.

Why this works: Beer has fermented sugars in it, which can act as natural fertilizer. The dying grass will feed on these sugars, detrimental fungi will die, and your lawn will start looking normal again.