What if the New York Times decided to host all ads themselves? nytimes.com/ad-42.jpg couldn't be distinguished from nytimes.com/todays-front-page-image.jpg
Obviously it's more likely for ad ad-provider like Google to do this, but even then, if there's new content from Google (say a blog post) I expect to be able to see it.
I'm pretty sure that /ad-.jpg or something like that is already a blocking pattern. But you're correct: I'm seeing ads on some smaller sites that host the ad banners on their own servers. And you know what? I'm okay with this. I explicitly use uMatrix instead of uBlock since blocking trackers and malware is more important to me than blocking ads. (Getting rid of the more annoying ads is a bonus, though, and I might change my mind if first-party ads become annoying, too.)
