alt Hacker NewsHow is it confusing? Most brick and mortar stores show ads for specific products. Online platforms other than Amazon do it too.
The only thing is that Amazon is more diversified than other retailers, in particular, they have AWS, essentially selling the platform that runs their website to third parties. It makes sense for them to offer sell their ad service to third parties too.
No one does it like Amazon, it requires users to walk through the sponsored ads before they can see organic search results, almost no other platform does this online. Walmart has a single strip of sponsored results at top, immediately leading to organic results, others like Target, HomeDepot do not mix in sponsored results with search results.
B&M is different, Ads are there, but you aren't forced to look at them like Amazon does.