Regarding “convincing someone to buy your product is not that easy”, I do agree with you, but at the same time, I remember all those products I’ve bought online. I did not search on Google for those products neither I went to the company websites to get information and buy. They were affiliate people and their blogs that inspired to buy them. PrettyLink Pro, SEO Pressor was recommended by Kimberley, I bought Profits Theme, WP Zon builder because Alex Whaley recommended. Similarly I bought CommentLuv Premium because Ileane, Kavita, Steve and many others were talking good about it.
Affiliate marketing overlaps with other Internet marketing methods to some degree, because affiliates often use regular advertising methods. Those methods include organic search engine optimization (SEO), paid search engine marketing (PPC – Pay Per Click), e-mail marketing, content marketing, and (in some sense) display advertising. On the other hand, affiliates sometimes use less orthodox techniques, such as publishing reviews of products or services offered by a partner.