Come on - the company spending the money has MORE visability into what their google ad spend buys them then in almost any other area.
I don't even care if I overpay on a "bid" for a spot - the metric I'm using is return on spend. And trust me, the mainline media companies driving this do not promise advertisers "fair" bidding. They have sales people trying to extract every nickle they can (through sometimes horrible accounting practices where they pay different divisions to drive up various "costs").