Potentially abusive ad network?
Really?
Surely it's just a matter of blocking ads using AdFree, AdBlocker, Adaware, etc....
Oh, but wait... Google removed all of those from the Play app store.
Thank Goodness for alternative sources.
For those who really want to know (and can be bothered), "Addons Detector" (which is available on the Play store) is a great way of seeing what's accumulated after all those impulsive (or not so) installs and enable the curious to ask questions like "why the heck does Words With Friends need the ability to send SMS messages?"
Spoiler: The answer is so that users can invite friends to play with them.