Since you're taking the example of Ebay. When Ebay doesn't pay for ads, the top paid result Amazon most of the time. When Amazon also runs out of ad money, it's

Since you're taking the example of Ebay. When Ebay doesn't pay for ads, the top paid result Amazon most of the time. When Amazon also runs out of ad money, it's a less reputable site taking the top site, sometimes a plain scam.