The other issue nowadays is all the reneging (from affiliate programs) going on. Forcing them to make informed opinion and deciding whether traffic is of value can be down to their advertising department.

I mean, when you see a billboard in the train station or other places, it isn't attatched to any affilate program.

Affiliate programs are becoming more problematic and their are not many you could actually trust in the long term --- Just read the threads on non payers - books deciding to change terms to the detriment of the website owner etc!

In my opinion this business will become a dinosaur !!