I used to work for an ad heavy mobile game and ad serving company couple of years ago, and I had ad blocking at dns level in my house. It blocks not only ads, but also most tracking and telemetry. My bosses wanted to know why my devices were not displaying ads or dialing back to home, they were pretty fucking puzzled. They were terrified others like me were around. Basically their entire business model depends of people not knowing how to block ads and telemetry