Perhaps, but Google has already been claiming[1] that such spending provides positive value (though I have no idea how true that is for whatever brands they're pursuing here)
Also it is generally really cheap to buy that ad, so even if the incremental value is small it is still worth it. It also keeps you on top of anyone else bidding on your brand, if you brand is generic enough for them to get away with it.
[1] http://searchengineland.com/ebay-says-adwords-ineffective-go... > On average, 50% of the ad clicks that occurred with a top rank organic result are incremental, i.e., they would not be recovered organically if the ad campaign is paused.