It isn&#x27;t so much a technical issue as it is one of trust and efficiency. GA is familiar, and easy to compare across different sites without worrying about <i>how</i> exactly they&#x27;re mining their logs. At best, they have to figure out how to make efficient comparisons. At worst, they have to worry about sites inflating their numbers--either through fabrication or just optimistic tweaking of how data is presented. With GA, they don&#x27;t really have to worry about outright fabrication or reliability. And while there&#x27;s a ton of data to be teased out of server logs--especially if someone tries to correlate it with other user data they already have--for most advertisers, that doesn&#x27;t really matter. They don&#x27;t want to invest the time it&#x27;d take to make use of it with all potential properties they want to advertise on.<p>Say what you will about GA and privacy issues, there&#x27;s a reason why it&#x27;s become so common place. Not just for site owners, but advertisers as well.