For personal sites like that, curators often do it for the love of the subject rather than a financial reward. Hence why some personal sites are hosted without any adverts.
Edit: I see I’m getting downvoted a lot for this comment. I appreciate creating content for the love of it might seem like an alien concept to many HNers but not everyone is driven by the motivation of turning every hobby into a start up. In fact once upon a time, in an era before Facebook and Google, the majority of an average persons surfing time was spent on non-commercial personal web sites.
