Earlier quoted context omitted.
Money. They’re faking ad delivery.
Do the ad suppliers have some sort of analytics in place to catch fraud like this? "This ip viewed 200 adds within 10 seconds!"
This issue is illuminated to some degree by 3rd party ad analytics companies that monitor this via crawlers and user panels. This problem is also attacked from the advertiser side that will use 'viewability' providers to ensure their ad is, well, viewed.