If those graphs are supposed to show that Google Shopping is an unpopular also-ran that users don't like or use, you have to wonder why they keep putting it in a big box with pictures at the top of search listings, like http://imgur.com/N3aGIVy
According to Google in the early days 'paid inclusion' was one of the original sins, and Google would never stoop that low. I personally think that paid inclusion is actually less evil than promoting your own crap products over the legitimate listings.
Isn't promoting your own crap just dogfooding paid inclusions?