They call it “dark traffic” - ads that are not seen by tech-savvy users who have excellent ad blockers.
Not surprised that its growing. The web is unusable without an ad blocker and its only getting worse, and will continue to get worse every month.
I use VLANs and different subnets for security. Having PiHole break randomly every few weeks and seeing the config is different when I didn’t change it was beyond frustrating, so I just gave up