Comparing GA reports to ad campaign reports from DSPs
I'm looking at an ad report from a DSP that shows a certain amount of clicks from a collection of zip codes - it looks great. But then I look at the GA report and it shows a ton of visits from places that were not specified in the ad campaign. I'm assuming that GA is showing the location of the ad server, and not the location of the end user.
But here's my question: if I'm using UTM why is GA looking at the location of the ad server and not the end user?