Many crypto companies have affiliate marketers who promote their services on various platforms and it has been the surest way of getting more audience. We still have a bunch of sites restricted strictly for gambling advertisements and gambling businesses in general
Those few successful affiliate marketers can be categorized into few like influencers that have a lot of audiences and as well as great bloggers.
They can always include their affiliate links and it works as their other source of income but in a passive and easy way after promoting it once.
^ There are various ways to have profit in joining the affiliating program, as we can see, there are too many reviews sites here that are being advertised for the sole purpose of making money through affiliation. Other people using it through blogs and vlogs, through social media by continuously posting frequently hoping that there are many people signing up using your reference information. But when it comes to income, I don't think it will become a passive income, probably just wasting of time.
It is still a passive income, as you've said about vlogs and blogs, they'll just put it one time and leave there for sure. And wait there are people that reads and watches their blogs and vlogs, as they've been entertained with that creator.
They're likely to sign up under their link so there's still an income, if it's a waste of time to you, that's okay but to those who are great affiliate marketers and creators, they got a good sideline by doing this.