This doesn't make any sense. Amazon can choose to pay Google per conversion instead of per click, but whether to send the conversion ping is already up to Amaz

This doesn't make any sense. Amazon can choose to pay Google per conversion instead of per click, but whether to send the conversion ping is already up to Amazon. They don't need to use something like Smile to get an excuse for not sending the ping: they can just not send the ping. (Why send pings at all? The reason to pay per conversion is to let Google optimize for sending you the cheapest traffic that converts. Your bids still end up in auctions against others, though, and if Google's estimate of how likely this traffic is to convert on your site is lower, the bids they'll put in on your behalf are lower, and you'll lose lots of auctions you'd have preferred to win.) I would also be surprised if Amazon were paying Google on a per-conversion basis, since I bet Amazon wants to do their optimization in-house. Now, if you said this was a sneaky way to cut down on their affiliate commissions that could make sense. (I used to work at Google, on display ads, but none of the above is based on internal information).