Of course it does'nt have to, however it is known that about all "generic" traffic will produce, is a high load on your server.  Unless you are just starting a new site, this kind of traffic is great to get your site noticed by some of the top search engines, and get some of your pay per impression programs working.  Other than that if you are trying to sell a real word, tangable good directly from your website you need to locate a vender that offiers targeted traffic.  You must find a reliable seller that also guarantee's a high percentage of uniqueness.

Hope this helps all you webbie's.