[thrdbndndn]

I actually don't believe so.

Not everything is priced on demand and supply -- at least not strictly.

Of course the potential of abuse is part of the equation, but I think Google (or similar large companies) simply has a guideline of how the amount of the bounty is decided, than surveying the market to see what its "actual value" is. It's not exactly a free market, at least not on Google's side.

[n2d4]

I assure you that when Google set those bounties, they thought about how much they would have to pay white hats to make them do the right thing. Of course, it's a highly illiquid market (usually there's just one seller and only a handful of buyers), and so the pricing is super inefficient (hence based on guidelines and not surveying on every individual bug), but the logic remains.