Sgt_Kickaxe - 7:03 pm on Nov 26, 2012 (gmt 0)
(although even Walmart and Target do that now)
ebay does it too, no site is sacred.
As for promoting affiliate offers through adwords, good luck with that. Possible small returns that can be turned off at any time vs huge probability of losing money... that's not ideal.
You have to find a more stable price source for traffic if you don't own the product, Facebook works for some.