I've been trying to come up with a better word for a while and I'm stuck. "Parasite" more accurately reflects the nature of the relationship between 'grifters' and the grifted. And alludes to ecological structure (polarization). But it's way too loaded for receptive purposes.
Plus, depending on the particular niché, there's another stage of development whereby they represent symbiotes. Like, Ben Shapiro isn't grifting everyone. Lots of them pay with eyes wide open for services provided -- patronage for saying things they want to say.