I think it's reasonable to assume that google would favor the Ad Sense customer given two results that are otherwise of equal or near equal quality but the notion that google would exclude good results from domains that do not serve Ad Sense ads is absurd.
Why is it absurd? If it's still considered the go-to option by most users, they could afford the slightly worse quality for the extra revenue, no? That's the end result of monopolies, the provider starts to compromise on the service to capitalize on the user's lack of viable options.
