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I get some of this type of traffic. It is coming from spammer sites.  These sites often look like a "directory" or they look like "search results".  They are usually running in industries where the cost of an adwords click is moderate to expensive.  They are always running ads - usually Adsense. I think that they operate in a few different ways... a) Dynamic site: you go there today and can't find a link.   That is because they are changing the data continuously - perhaps daily or by visitor.  The might think that changing the data on the site continuously will help it survive in the SERPs.    Look at this site today, then go back in a day or two, you will likely see that it is completely different,  sometimes it will "look" identical, but the destination of the links have changed. b) Referral log spammers:  there never was a link to you on their site.  They have a computer program sending a "visitor" to your site so that they appear in your referral log.  They are doing this in industries where people pay a lot of money for clicks and pay really close attention to their visitors.  They know that you will come looking.   They hope that you will click on their ads. c) Malware trap:  another referral log scheme to get staff from a high value business, maybe a competitor, to visit their site.  That referral in your log was "bait" and you are stepping into a malware trap. A small business in a high value niche is the most lucrative and vulnerable malware target.  Staff who are chasing reefers have access to adwords accounts, adsense accounts, checking accounts, credit card with high limits, they got your name, address and zip code. d) Adsense/Adword:  these sites display Adsense.  Yesterday a visitor, genuine or robotic, was on their site and "clicked" your ad.  That produced a visitor to your site and income for their site. e) Combinations of the above:   Two or three of the methods above are all being used. Be careful.