If they are doing exactly what they say they are. It could actually be legal. In which case they wouldn't set up crap sites because that would be unethical. However I would never chance it because I doubt they're telling the truth. I recommend you avoid it, inform Google and maybe ask and post their opinion.
Don't do it. If you're very lucky like me you'll get a warning along these lines: It has come to our attention that invalid clicks or impressions have been generated on the Google ads on your site(s) through users of third-party programs paid or provided with other incentives to visit your site. Such programs may include, but are not limited to auto-surf, pay-to-surf, pay-to-read, or pay-to-click sites. I got a second chance and I wasn't kicked out. You might not be so lucky.
I saw a few posts similar to this one. One claimed that these kinds of sites (This particular one has not yet been proven to be fraudulent in anyway) will cause Google to "drop" Adsense. They're not going to suddenly "drop" Adsense. That's ridiculous. Worst case scenario, Adsense will be starved into a famished state by upcoming competitive alternatives.
Google is pretty hard when it comes to this kind of service. If you have any serious plans with adsense then stay away. Google seems to have some good filters to find traffic comes from this kind of source, the google help forums are full of whining people with disabled accounts for this reason. And you don't get a second chance from google.
Sounds like a real great way to get a lifetime ban from Google and Adsense. Better don't try this unless you want to risk that, SY
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