Amazon offers small discount to users of A9.com search engine

This evening, when browsing Amazon.com, I noticed an odd logo on their pages.

Clicking the link brought me to this page.

For those of you who may not be able to see that page, here is the first paragraph.

Douglas E. Welch, since you've been using A9.com recently, virtually everything at Amazon.com is automatically an additional π/2% (1.57%) off for you. Collecting this discount is zero effort on your part. It will be applied automatically at checkout (it will happen whether you use the shopping cart or our 1-Click Shopping®). You don't need to do anything to get this discount except keep using A9.com as your regular search engine

It is a small discount, but I will take it just for occasionally using the A9 search engine.