As I said before, the PPC affiliates are just redistributors. The only real losers, in terms of traffic, are the competing SEOs.
I would also like to point out that some of the "affiliate" based sites do show a good number of non-commercial, non-PPC, organic results as well, although most affiliates admittedly show straight PPC results.
Seeing as they are optimised for any keyword you can think of maybe I would not of had these extra visitors if these type of sites were not ranking as high as they are
So yes they have helped a little in sending visitors to a information site
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