Why Hire Great Hackers?
Here's one possible reason you want to hire great hackers. GHs are motivated by more than money. The fact is, if you don't hire them, they're going to go off and hack anyway. If you don't hire them, they might even just go off and hack up a free competitor to your product.
So maybe you need to hire GHs defensively (a bit like Software Patents), as insurance. At least you'll focus their attention on your product / ecosystem. Even if they don't do much for it, they're unlikely to do anything against it.
More insights : ThoughtStorms: GreatHackers