Isn't paying for sponsored results more or less equivalent to paying for better shelf space? The space may not "really" be limited, but for practical purposes, the second page of search results barely exists.
Not really because even then you could be trumped by an amazon basics result without realizing what happened unless you are checking for this constantly yourself. When you pay for premium shelf space you are paying for the explicit shelf in the explicit store, everything is exactly planned, nothing left to chance or uncertainty, its all very diplomatic in comparison.
