To demonstrate the way it blinds people to options: What you mean is running 3rd party ads via ad networks. It's perfectly feasible to show an image that link

To demonstrate the way it blinds people to options: What you mean is running 3rd party ads via ad networks. It's perfectly feasible to show an image that links to some advertiser's site for a negotiated fee. This is the equivalent of a paper magazine with advertisements. Not renting out injection points to executing whatever foreign code on their visitor's devices. My ad blocker won't even block it (well not by default, and only as long as you play nice, it's not like online advertising has any goodwill left over, or ever acted to deserve it).