I haven't played that game in a long time, but back then they were the sole determiners of whether a "click" was valid or not. I got charged for clicks for which people only stayed for a second or so. Now there were a lot of people who claimed they can make a decision about purchasing from a website in a second, but I don't think they're thinking it through. I think they were erroneous clicks or competitors, yet I was charged.

They may have improved.