Amazon ads on the site have underperformed badly in recent years. Click rates have been steady but conversions are now dead.
This suggests there may be bots that generate clicks on referral links here and there to make ad users tend to hope for the best. The cynic suggests Amazon themselves are more than likely with their crawlers etc.
The footer ads have been more consistent. The earnings are minimal but at least there are a few pounds of rice to eat here and there. Peanuts are cheap too.
Given the possibility of click bots attacking Amazon ads suggests an alternative is probably due. The conversion with the Best Buy ads also went nowhere. That operation needs an overhaul as the reporting is very poorly designed.