I don't know how technically hard this would be to implement. Or what business model will resist adding it. I just know that most of my web searches are NOT me trying to buy stuff. They're usually looking up information.
Like, how does the load sensing algorithm work on my LG washer? No chance I'll ever find out by searching the web. Only 200 links to different places I can buy a new one. Or maybe some videos explaining that the feature exists, and "oh and would you like to buy one?"
Maybe I want to know if my GadgetMaster 3000 will work with my WidgetWanker Mark II. Nope, but here's 100 places you can buy those, or maybe the THINGDOODLE brand of knockoffs.
Ok, I'm ranting. Point is: give me a way to restrict my search to only those pages that aren't selling anything. Maybe the heuristic is that the page hasn't changed in 6 months, or uses outdated tags like <marquee>, or some fancy semantic analysis of the page copy. I don't know. I just wish search results weren't so utterly dominated by e-commerce sites or affiliate spam.