As a merchant I have observed that PPC Affiliates usually asks for more commission, this make sense too because if they are spending on Keyword bidding then radically their operating cost increases that’s why they ask for more commission.
My Question is should we give concern over such requests because this strategy will lower the revenue and competition with same keywords in which we are doing PPC. How to discriminate? Will PPC affiliate give a thought to not to bid on Company’s own bidding keywords?
Wait!
Are you trying to say that you’re the PPC advertiser as well as the Adsense publisher hence spending your own dollar and making commission over it?
This is a funny scenario never heard…
Or are you an Adsense publisher and want to get increased commission because advertisers are paying more CPC? Then I guess this is a legitimate demand but Google would loose a lot of money. But they would make up by increasing the CPCs 
Regards,