Protection of one's attention is our generation's luxury product.
Whether it's the TV hardware or the streaming service in your house, your standard of living is now judged by whether you pay extra for the ad-free tier.
Apple tends to skew luxury purchase, so it makes sense it hasn't been riddled with adware yet. The Apple logo is a status symbol that you're not being bombarded with ads in every corner of underutilized screen real-estate.