Second, a big part of being native is letting the right advertisers find you. This is what I mean about being patient. It may be hard to picture now, 10 years later but Google initially had the same problem. The real advertising budgets were looking to replace/augment their TV & poster campaigns. Advertisers were FMCGs (detergents, coca cola), cars, movies, etc. Local pilates instructors & 2 man shop insurance resellers didn't have advertising budgets. No one was searching for "what is the most refreshing drink?" so any ad for coca cola would be "non-ative" (BTW I really like this description here - thanks the_watcher).
BTW, buying is not a huge part of adwords. In fact, it's pretty hard to get a positive ROI on a "product" purchase campaign.
To give you an example, if you want to run a one off event that's good for parents with kids, Facebook is awesome. It would probably also work well for showing film trailers, showing stand up or theatre "trailers." etc.
If I understand you correctly you are talking about how adwords link to marketing landing pages that _give away_ something valuable to the user like an ebook in exchange for your email address. In this way they convert you by slowly giving away more value, building trust, and upselling premium offerings, etc.